291 results on '"Marie, Guillaume"'
Search Results
252. Annuaire des Côtes-du-Nord / par MM. Habasque, Marée, de Garaby
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Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, Société archéologique et historique des Côtes-du-Nord. Auteur du texte, Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, and Société archéologique et historique des Côtes-du-Nord. Auteur du texte
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1846, 1846 (A11)., Appartient à l’ensemble documentaire : Bretagn1
253. Les Hommes de 1793, satyre, par Fois-Mie-Gme Duault
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Duault, François-Marie-Guillaume (1757-1833). Auteur du texte and Duault, François-Marie-Guillaume (1757-1833). Auteur du texte
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Avec mode texte
254. Miracles et merveilles arrivés dans l'église Notre-Dame de Ceignac . Augmenté d'un traité de pèlerinage... Nouvelle édition, sur copie imprimée de 1660
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Rudelle, Marie-Guillaume de. Auteur présumé du texte, Mazeau, Jean. Auteur présumé du texte, Rudelle, Marie-Guillaume de. Auteur présumé du texte, and Mazeau, Jean. Auteur présumé du texte
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Contient une table des matières, Avec mode texte
255. Conférence Montesquieu. Discours prononcé à la séance de rentrée, le vendredi 4 décembre 1868, par M. Feuilloley,...
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Conférence Montesquieu. Éditeur scientifique, Feuilloley, Marie Guillaume Germain (1845-1930). Auteur du texte, Conférence Montesquieu. Éditeur scientifique, and Feuilloley, Marie Guillaume Germain (1845-1930). Auteur du texte
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Avec mode texte
256. Les Mille et une chansons de Jeanne et de Marie Ayral
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Ayral de Magnas, Jeanne Contensous (dame Brunel, puis Duval). Auteur du texte, Ayral Bonneville, Marie-Guillaume. Auteur du texte, Ayral de Magnas, Jeanne Contensous (dame Brunel, puis Duval). Auteur du texte, and Ayral Bonneville, Marie-Guillaume. Auteur du texte
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Avec mode texte
257. La Homeopatía al alcance de todos
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Pita, Manuel, imp, Devergie, Marie Guillaume Alphonse, 1798-1879, Pita, Manuel, imp, and Devergie, Marie Guillaume Alphonse, 1798-1879
258. Annuaire des Côtes-du-Nord / par MM. Habasque, Marée, de Garaby
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Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, Société archéologique et historique des Côtes-du-Nord. Auteur du texte, Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, and Société archéologique et historique des Côtes-du-Nord. Auteur du texte
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1868, 1868 (A33,NOUV SER,T18)., Appartient à l’ensemble documentaire : Bretagn1
259. Annuaire des Côtes-du-Nord / par MM. Habasque, Marée, de Garaby
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Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, Société archéologique et historique des Côtes-du-Nord. Auteur du texte, Habasque, François-Marie-Guillaume (1788-1855). Auteur du texte, Marée. Auteur du texte, Garaby, Malo-Joseph de (1797-1855). Auteur du texte, and Société archéologique et historique des Côtes-du-Nord. Auteur du texte
- Abstract
1847, 1847 (A12)., Appartient à l’ensemble documentaire : Bretagn1
260. Risk Factors for Acute Choroidal Ischemia after Intra-arterial Melphalan for Retinoblastoma: The Role of the Catheterization Approach.
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Stathopoulos, Christina, Bartolini, Bruno, Marie, Guillaume, Beck-Popovic, Maja, Saliou, Guillaume, and Munier, Francis L.
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CATHETERIZATION , *INTERNAL carotid artery , *MELPHALAN , *RETINOBLASTOMA , *LOW vision , *FLUORESCENCE angiography , *OSTEOARTHRITIS - Abstract
To identify risk factors for acute choroidal ischemia (ACI) after intra-arterial chemotherapy (IAC) for retinoblastoma. Retrospective cohort study. Two hundred twenty patients (248 eyes) treated with IAC in Lausanne between November 2008 and September 2019 (665 procedures). All patients were evaluated on a monthly basis with fundus photography and fluorescein angiography before and after each IAC injection. Acute choroidal ischemia, defined as any new choroidal ischemia clinically diagnosed within 35 days after an IAC injection, were noted. Eyes with choroidal complications diagnosed later than 35 days after the last IAC injection (n = 7) or those for which the status of the choroid was not assessable (n = 35) were excluded. Specific procedure parameters and treatment regimens were compared between the group of eyes with and without ACI. Procedure-related risk factors for ACI after IAC injection and visual acuity assessment in the group of eyes with ACI. Acute choroidal ischemia developed in 35 of 206 included eyes after a mean of 2 injections. No differences were found between the two study groups regarding age at first IAC injection, disease grouping at diagnosis, previously administered treatments, number of IAC injections, drug dose, mean injection time, injection method (pulsatile vs. continuous), or concomitant intravitreal melphalan use. Treatment regimen (melphalan vs. combined melphalan plus topotecan; P < 0.05), catheterization route (internal carotid artery vs. external carotid or posterior communicating artery; P < 0.001), and catheterization type (occlusive into the ophthalmic artery [OA] vs. nonocclusive; P < 0.001) were included in multivariate analysis, and occlusive catheterization was identified as an independent risk factor for ACI (P < 0.001). In the subgroup undergoing an occlusive procedure, placement of the catheter tip into the OA distal third versus medial and proximal thirds (P = 0.04) and a mean catheter diameter-to-OA lumen ratio of 0.6 or more (P < 0.001) were correlated significantly with ACI. Complete vision loss was noted in 27% of the eyes with ACI that were old enough for visual assessment (n = 9/33), whereas 33% maintained a useful vision ranging between 0.1 and 0.8 (n = 11/33). Catheterization of the OA should be attempted from an ostial position or an external carotid approach to minimize the risk of potentially vision-threatening choroidal complications. [ABSTRACT FROM AUTHOR]
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- 2021
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261. An older woman with herpes zoster ophthalmicus complicated by orbital apex syndrome.
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Marie, Guillaume and Scheffler, Max
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AMOXICILLIN , *ANTIVIRAL agents , *EXOPHTHALMOS , *ORBITAL diseases , *MAGNETIC resonance imaging , *VISION disorders , *OPHTHALMIC zoster , *PARESTHESIA , *SURGICAL decompression , *EYE pain , *DISEASE complications , *OLD age , *THERAPEUTICS - Abstract
The article describes the case of a 76-year-old woman with herpes zoster ophthalmicus complicated by orbital apex syndrome. Case highlights include oral famciclovir and amoxicillin given for herpes zoster ophthalmicus, varicella zoster virus according to polymerase chain reaction in cerebrospinal fluid, and the impact of ischaemic stroke with right hemiplegia on the patient's progress.
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- 2018
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262. Passer la sylviculture dans la tordeuse : évaluation des traitements préventifs face aux pertes de bois liées à la tordeuse des bourgeons de l'épinette
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Sainte-Marie, Guillaume
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- Tordeuse des bourgeons de l'épinette, Traitement sylvicole, Conifères -- Maladies et fléaux -- Prévention -- Évaluation, Aménagement forestier, Succession forestière, Vulnérabilité
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Il est généralement attendu qu'au Québec, l'épidémie en cours sera moins sévère que la dernière. Cette croyance se base sur deux raisons principales : le jeune âge des peuplements de sapin actuels réduisant leur vulnérabilité et la proportion croissante d'espèces feuillues dans les sapinières, les feuillus étant reconnus pour créer un effet protectif contre la défoliation par la TBE par le biais d'une plus grande abondance d'ennemis naturels et de barrière potentielle à la dispersion de la TBE. Plusieurs modifications de la composition et de la structure sont survenues dans les dernières décennies et les traitements sylvicoles préventifs, principalement des manipulations de composition, appliqués depuis la dernière épidémie de TBE font partie de ces changements. Or, l'ampleur et les effets de ces manipulations de composition demeurent méconnus. Afin d'évaluer l'efficacité des traitements préventifs face aux dommages potentiels par la TBE, nous avons analysé l'historique de perturbation récent d'un secteur intensivement aménagé de la Gaspésie. Nous avons utilisé les données de la base de données SIFORT et simulé les effets d'épidémies de TBE afin de déterminer la vulnérabilité de la forêt à partir des conditions forestières observées tôt dans la dernière épidémie de TBE (1985) et 12 ans après cette dernière (2004). Les résultats de ces simulations ont montré que l'approche visant à augmenter l'abondance d'épinette noire est la plus efficace pour diminuer les pertes en volume liées à la TBE, mais que d'importants efforts de gestion de la végétation compétitrice sont nécessaires dans ces peuplements. Par ailleurs, nous avons également observé une importante régénération feuillue suite à l'épidémie de TBE, mais également suite à la récolte de bois. La question de la durabilité de l'aménagement forestier est donc apparue importante suite aux signes de perte de rendement en bois résineux observés en Gaspésie. Nous avons alors analysé les changements de composition après TBE et coupe forestière le long d'un gradient longitudinal de la sapinière du Québec, dans 3 sites allant d'un climat continental, où les feuillus dominent, à un climat maritime, où le sapin baumier domine. Les analyses ont été effectuées à partir de la base de données SIFORT, où les inventaires de 1972-74 et ceux de 2004-2006 ont été comparés en termes de composition. Les résultats montrent que l'important enfeuillement observé, particulièrement en Gaspésie, est probablement localisé et temporaire, dû à la prédominance du modèle successionnel alternant entre dominance mixte et sapin dans cette région dominée par le sapin baumier avant la dernière épidémie de TBE. Par ailleurs, la composition régionale s'est avérée un facteur important pour prédire la succession après perturbation, qui est apparue très similaire tant après coupe qu'après TBE. Les coupes forestières ne seraient donc pas la principale cause d'enfeuillement depuis la dernière épidémie, allant jusqu'à améliorer le rendement résineux après coupe dans les régions à forte proportion de feuillus. À plus long terme, la question de la dynamique de perturbation se complexifie en considérant la succession d'épidémies de TBE et la suite de traitements sylvicoles en parallèles. Les résultats obtenus précédemment provenant d'un contexte d'épidémie unique, nous avons poussé l'évaluation des différentes approches de sylviculture préventive et effectué des simulations d'aménagement pour des séries de trois épidémies successives à partir du modèle de dynamique forestière LANDIS-II, implémenté sur un territoire du centre du Québec. Nos simulations d'aménagement intensif d'épinette à long terme ont montré une grande efficacité à diminuer la vulnérabilité à grande échelle, mais dans ce cas, une gestion de la végétation efficace était essentiellement implicite dans le modèle, compte tenu du faible envahissement par la végétation compétitrice par rapport à ce que nous avons observé au Québec depuis la dernière épidémie. L'aménagement extensif (sans plantation ou éclaircie), en permettant le maintien de feuillus après coupe, s'est également avéré efficace dans l'ensemble pour réduire la vulnérabilité des forêts, mais son efficacité à augmenter le rendement résineux après épidémie dépendrait largement de la composition avant coupe. Cette thèse montre donc que l'approche préventive s'avère globalement efficace, mais que le contexte local et régional doit être tenu en compte et que cet aménagement doit, par conséquent, être utilisé avec précaution. De surcroît, il faudrait possiblement concentrer les efforts d'aménagement intensif sur un nombre plus restreint de peuplements afin de limiter la végétation compétitrice, potentiellement où les gains seraient les meilleurs, donc dans les secteurs les plus productifs. Il en ressort donc que l'aménagement tel que pratiqué actuellement, avec sa diversité de traitements ayant des avantages différents et complémentaires, n'est pas si mauvais en soi d'un point de vue général. Ces aspects, parallèlement à la redéfinition des traitements sylvicoles pour optimiser la quantité de feuillus et augmenter leur efficacité, constituent sans aucun doute les principales recommandations à tirer de cette thèse. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Tordeuse des bourgeons de l'épinette, sylviculture, aménagement extensif, protection des forêts, succession forestière, vulnérabilité des forêts, effet de protection des feuillus.
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- 2018
263. Author Correction: Trade-offs in using European forests to meet climate objectives
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Luyssaert, Sebastiaan, Marie, Guillaume, Valade, Aude, Chen, Yi-Ying, Djomo, Sylvestre Njakou, Ryder, James, Otto, Juliane, Naudts, Kim, Lansø, Anne Sofie, Ghattas, Josefine, and McGrath, Matthew J.
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In this Letter, in “About 75% of this reduction is expected to come from emission reductions and the remaining 25% from land use, land-use change and forestry”, ‘25%’ should read ‘1%’ and '75%' should read '99%'. In the sentence “The carbon-sink-maximizing portfolio has a small negative effect on annual precipitation (−2 mm) and no effect on air temperature (Table 1)” the word ‘precipitation’ was omitted. Denmark was accidentally deleted during the conversion of Fig. 1. The original Letter has been corrected online.
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- 2019
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264. Exploration of new methods involved for the synthesis of PET tracers
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Marie, Guillaume
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- 547, QD Chemistry
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This work describes the development and the optimisation of microfluidic radiolabelling by using an Eckert & Ziegler device remotely controlled by a computer to perform the multistep synthesis of [18F]-fluoro-2-deoxy-D-glucose ([18F]-FDG). This device was then modified to control the fluidic transfers via flow of nitrogen and vacuum with the aid of a new one-way cassette system by using different concentrations of water for the Kryptofix solution. A new route was also explored to perform florbetaben ([18F]-BAY94- 9172), a potent Alzheimer’s disease PET tracer. Chapter 1 is an overview of positron emission tomography techniques to synthesise tracers. Chapter 2 is a brief introduction of the PETIC centre (Wales), where the fluoride-18 was delivered to produce [18F]-FDG. Chapter 3 describes the reaction of the [K+⊂2.2.2]18F− complex on mannose triflate and the variety of products formed. The Eckert & Ziegler platform was furnished with a cassette module and a microfluidic tubing to perform the radiolabelling fluorination of mannose triflate to the tetraacetate [18F]-deoxy-D-glucose and [18F]-FDG. Chapter 4 is focused on the modifications on the Eckert & Ziegler modules by using 1-way cassettes to limit the use of mechanical valves. [18F]-FDG was synthesised via a semiautomated procedure by limiting the number of modules present in the hot cell. Chapter 5 is an investigation for the preparation of several triethylene glycol derivatives following the syntheses of Kryptofix [2.2.2]. The use of triethylene glycol chain will be essential for the synthesis of the Florbetaben precursor. The Chapter 6 is the exploration of a new synthetic route leading to the precursor of florbetaben.
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- 2014
265. Ammonium CI-Orbitrap: a tool for characterizing the reactivity of oxygenated organic molecules.
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Dandan Li, Dongyu Wang, Caudillo, Lucia, Scholz, Wiebke, Mingyi Wang, Tomaz, Sophie, Marie, Guillaume, Surdu, Mihnea, Eccli, Elias, Xianda Gong, Gonzalez-Carracedo, Loic, Granzin, Manuel, Pfeifer, Joschka, Rörup, Birte, Schulze, Benjamin, Rantala, Pekka, Perrier, Sébastien, Hansel, Armin, Curtius, Joachim, and Kirkby, Jasper
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CHEMICAL ionization mass spectrometry , *MASS spectrometry , *TIME-of-flight mass spectrometers , *MASS spectrometers , *ATMOSPHERIC aerosols , *PINENE , *NUCLEAR research - Abstract
Oxygenated organic molecules (OOMs) play an important role in the formation of atmospheric aerosols. Due to various analytical challenges in measuring organic vapors, uncertainties remain in the formation and fate of OOMs. The chemical ionization Orbitrap mass spectrometer (CI-Orbitrap) has recently been shown to be a powerful technique able to accurately identify gaseous organic compounds due to its great mass resolving power. Here we present the ammonium ion (NH4+) based CI-Orbitrap as a technique capable of measuring a wide range of gaseous OOMs. The performance of the CI-(NH4+)-Orbitrap was compared with that of state-of-the-art mass spectrometers, including a nitrate ion (NO3-) based CI coupled to an atmospheric pressure interfaced to long time-of-flight mass spectrometer (APi-LTOF), a new generation of proton transfer reaction-TOF mass spectrometer (PTR3-TOF), and an iodide (I-) based CI-TOF mass spectrometer equipped with a Filter Inlet for Gases and AEROsols (FIGAERO-CIMS). The instruments were deployed simultaneously in the Cosmic Leaving OUtdoors Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN) during the CLOUD14 campaign in 2019. Products generated from α-pinene ozonolysis across multiple experimental conditions were simultaneously measured by the mass spectrometers. NH4+-Orbitrap was able to identify the widest range of OOMs (i.e., O = 2), from low oxidized species to highly oxygenated volatile organic compounds (HOM). Excellent agreements were found between the NH4+-Orbitrap and the NO3--LTOF for characterizing HOMs and with the PTR3- TOF for the less oxidized monomeric species. A semi-quantitative information was retrieved for OOMs measured by NH4+-Orbitrap using calibration factors derived from this side-by-side comparison. As other mass spectrometry techniques used during this campaign, the detection sensitivity of NH4+-Orbitrap to OOMs is greatly affected by relative humidity, which may be related to changes in ionization efficiency and/or multiphase chemistry. Overall, this study shows that NH4+ ion46 based chemistry associated with the high mass resolving power of the Orbitrap mass analyzer can measure almost all-inclusive compounds. As a result, it is now possible to cover the entire range of compounds, which can lead to a better understanding of the oxidation processes. [ABSTRACT FROM AUTHOR]
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- 2023
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266. Using GIS and Multicriteria Analysis to Map Flood Risk Areas of the Tongo Bassa River Basin (Douala, Cameroon).
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Essoh, Willy Sone, Onguene, Raphael, Ndongo, Barthelemy, Nshagali, Georges, Colmet-Daage, Antoine, Marie, Guillaume, Iroume, Junior, Stieglitz, Thomas, Besack, Felix, Ewoukem, Thomas Efole, Eyango, Minette Tomedi, Etame, Jacques, and Braun, Jean Jacques
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FLOOD risk , *GEOGRAPHIC information systems , *WATERSHEDS , *FLOODS , *ANALYTIC hierarchy process , *LITERATURE reviews , *METROPOLIS - Abstract
Sone Essoh, W.; Onguene, R.; Ndongo, B.; Nshagali, G.; Colmet-Daage, A.; Marie, G.; Iroume, J.; Stieglitz, T.; Besck, F.; Efole Ewoukem, T.; Tomedi Eyango, M.; Etame, J., and Braun, J.J., 2023. Using GIS and multicriteria analysis to map flood risk areas of the Tongo Bassa River Basin (Douala, Cameroon). Journal of Coastal Research, 39(3), 531–543. Charlotte (North Carolina), ISSN 0749-0208. The present study aimed to map the areas at risk of flooding in the Tongo Bassa watershed (42 km2) located in the heart of the Cameroonian economic capital (Douala) in the tropical zone of Central Africa, more precisely in the Wouri Estuary, at the bottom of the Gulf of Guinea. Like most of the world's major cities, Douala is subject to floods. The methodological approach was to identify the flooding risk determinants in the area from an extensive literature review and field surveys and then analyze these factors and map areas at risk of flooding using the analytical hierarchy process approach coupled with the GIS environment. The results revealed that four parameters of the natural environment (elevation, drainage density, distance to the river, and land cover) were the factors that mainly influenced the phenomenon of flooding in the region. Three major classes of flood risk were highlighted: low risk, medium risk, and high risk. To validate the effectiveness of the flood risk map obtained, the flood points collected in the field were cross-checked for ground truth after a flood occurred in the watershed. This cross-check between the resulting map and the flood points using GIS tools showed a good representation of the flooded area. This result is quite interesting because the areas where the risk of flooding is high are consistent with those where flooding is most frequent. The presented results constitute a basic decision support tool for the management of flood zones by the public authorities and the decentralized territorial communities of the city of Douala. [ABSTRACT FROM AUTHOR]
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- 2023
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267. Prendre en compte le patrimoine maritime culturel
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Péron, Françoise, Marie, Guillaume, Littoral, Environnement, Télédétection, Géomatique (LETG - Brest), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), and Université de Nantes (UN)-Université de Nantes (UN)
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[SHS.MUSEO] Humanities and Social Sciences/Cultural heritage and museology ,[SHS.GEO] Humanities and Social Sciences/Geography ,GIZC ,[SHS.GEO]Humanities and Social Sciences/Geography ,patrimoine maritime culturel ,[SHS.MUSEO]Humanities and Social Sciences/Cultural heritage and museology ,ComputingMilieux_MISCELLANEOUS ,politiques publiques - Abstract
National audience
- Published
- 2009
268. Vitesses d'évolution et dynamiques des falaises basaltiques de l'île d'Hawaï
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Guillaume Marie, Marie, Guillaume, Littoral, Environnement, Télédétection, Géomatique (LETG - Brest), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN), and Université de Nantes (UN)-Université de Nantes (UN)
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[SDU.STU.GM] Sciences of the Universe [physics]/Earth Sciences/Geomorphology ,Delta de lave ,media_common.quotation_subject ,[SHS.GEO] Humanities and Social Sciences/Geography ,Geography, Planning and Development ,Cliff ,Glissements ,0211 other engineering and technologies ,0507 social and economic geography ,02 engineering and technology ,Sea arch ,Hawaii ,Volcanic coasts ,Lava delta ,Collapses ,Slides ,Hawaï ,14. Life underwater ,[SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology ,media_common ,Effondrements ,Falaise ,Côtes volcaniques ,Arche ,05 social sciences ,021107 urban & regional planning ,Art ,[SHS.GEO]Humanities and Social Sciences/Geography ,050703 geography ,Humanities - Abstract
Lava deltas, built when lava flows arrive into the ocean, quickly retreat of several dozens of meters a year by landslides of the hyaloclastic base and marine attack. The retreat of the cliff is degressive and slows after few years. When the delta is stabilized, about ten years after its building, the retreat of the cliff is slower, but the joints of the lava make it easier. The wave attack causes rock slides, pavement erosion, topple and rockfalls. The sea caves can evolve into blowholes or sea archs by collapse of the roof or intersection of adjacent caves., Les deltas de lave, créés lors de l'arrivée de coulées de lave dans l'océan, reculent rapidement de plusieurs dizaines de mètres par an sous l'action conjointe des glissements de terrain du soubassement hyaloclastique et de l'attaque marine. Le recul de la falaise est dégressif et ralentit au bout de quelques années. Une fois le delta stabilisé, une dizaine d'années après sa formation, le diaclasage de la lave va contribuer au recul plus lent de la falaise sous les coups de boutoir des vagues, provoquant éboulement, dépavage, basculements et écroulements. Les grottes marines peuvent évoluer en trous souffleurs ou en arches par effondrement de la voûte ou recoupement de grottes adjacentes., Marie Guillaume. Vitesses d'évolution et dynamiques des falaises basaltiques de l'île d'Hawaï. In: Hommes et Terres du Nord, 2003/1. Dynamique et gestion des côtes à falaise, sous la direction de Guillaume Pierre et Philippe Lahousse. pp. 2-11.
- Published
- 2003
269. Temperature, humidity, and ionisation effect of iodine oxoacid nucleation.
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Rörup B, He XC, Shen J, Baalbaki R, Dada L, Sipilä M, Kirkby J, Kulmala M, Amorim A, Baccarini A, Bell DM, Caudillo-Plath L, Duplissy J, Finkenzeller H, Kürten A, Lamkaddam H, Lee CP, Makhmutov V, Manninen HE, Marie G, Marten R, Mentler B, Onnela A, Philippov M, Scholz CW, Simon M, Stolzenburg D, Tham YJ, Tomé A, Wagner AC, Wang M, Wang D, Wang Y, Weber SK, Zauner-Wieczorek M, Baltensperger U, Curtius J, Donahue NM, El Haddad I, Flagan RC, Hansel A, Möhler O, Petäjä T, Volkamer R, Worsnop D, and Lehtipalo K
- Abstract
Iodine oxoacids are recognised for their significant contribution to the formation of new particles in marine and polar atmospheres. Nevertheless, to incorporate the iodine oxoacid nucleation mechanism into global simulations, it is essential to comprehend how this mechanism varies under various atmospheric conditions. In this study, we combined measurements from the CLOUD (Cosmic Leaving OUtdoor Droplets) chamber at CERN and simulations with a kinetic model to investigate the impact of temperature, ionisation, and humidity on iodine oxoacid nucleation. Our findings reveal that ion-induced particle formation rates remain largely unaffected by changes in temperature. However, neutral particle formation rates experience a significant increase when the temperature drops from +10 °C to -10 °C. Running the kinetic model with varying ionisation rates demonstrates that the particle formation rate only increases with a higher ionisation rate when the iodic acid concentration exceeds 1.5 × 10
7 cm-3 , a concentration rarely reached in pristine marine atmospheres. Consequently, our simulations suggest that, despite higher ionisation rates, the charged cluster nucleation pathway of iodic acid is unlikely to be enhanced in the upper troposphere by higher ionisation rates. Instead, the neutral nucleation channel is likely to be the dominant channel in that region. Notably, the iodine oxoacid nucleation mechanism remains unaffected by changes in relative humidity from 2% to 80%. However, under unrealistically dry conditions (below 0.008% RH at +10 °C), iodine oxides (I2 O4 and I2 O5 ) significantly enhance formation rates. Therefore, we conclude that iodine oxoacid nucleation is the dominant nucleation mechanism for iodine nucleation in the marine and polar boundary layer atmosphere., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2024
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270. Assessing the importance of nitric acid and ammonia for particle growth in the polluted boundary layer.
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Marten R, Xiao M, Wang M, Kong W, He XC, Stolzenburg D, Pfeifer J, Marie G, Wang DS, Elser M, Baccarini A, Lee CP, Amorim A, Baalbaki R, Bell DM, Bertozzi B, Caudillo L, Dada L, Duplissy J, Finkenzeller H, Heinritzi M, Lampimäki M, Lehtipalo K, Manninen HE, Mentler B, Onnela A, Petäjä T, Philippov M, Rörup B, Scholz W, Shen J, Tham YJ, Tomé A, Wagner AC, Weber SK, Zauner-Wieczorek M, Curtius J, Kulmala M, Volkamer R, Worsnop DR, Dommen J, Flagan RC, Kirkby J, McPherson Donahue N, Lamkaddam H, Baltensperger U, and El Haddad I
- Abstract
Aerosols formed and grown by gas-to-particle processes are a major contributor to smog and haze in megacities, despite the competition between growth and loss rates. Rapid growth rates from ammonium nitrate formation have the potential to sustain particle number in typical urban polluted conditions. This process requires supersaturation of gas-phase ammonia and nitric acid with respect to ammonium nitrate saturation ratios. Urban environments are inhomogeneous. In the troposphere, vertical mixing is fast, and aerosols may experience rapidly changing temperatures. In areas close to sources of pollution, gas-phase concentrations can also be highly variable. In this work we present results from nucleation experiments at -10 °C and 5 °C in the CLOUD chamber at CERN. We verify, using a kinetic model, how long supersaturation is likely to be sustained under urban conditions with temperature and concentration inhomogeneities, and the impact it may have on the particle size distribution. We show that rapid and strong temperature changes of 1 °C min
-1 are needed to cause rapid growth of nanoparticles through ammonium nitrate formation. Furthermore, inhomogeneous emissions of ammonia in cities may also cause rapid growth of particles., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2024
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271. Nitrate Radicals Suppress Biogenic New Particle Formation from Monoterpene Oxidation.
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Li D, Huang W, Wang D, Wang M, Thornton JA, Caudillo L, Rörup B, Marten R, Scholz W, Finkenzeller H, Marie G, Baltensperger U, Bell DM, Brasseur Z, Curtius J, Dada L, Duplissy J, Gong X, Hansel A, He XC, Hofbauer V, Junninen H, Krechmer JE, Kürten A, Lamkaddam H, Lehtipalo K, Lopez B, Ma Y, Mahfouz NGA, Manninen HE, Mentler B, Perrier S, Petäjä T, Pfeifer J, Philippov M, Schervish M, Schobesberger S, Shen J, Surdu M, Tomaz S, Volkamer R, Wang X, Weber SK, Welti A, Worsnop DR, Wu Y, Yan C, Zauner-Wieczorek M, Kulmala M, Kirkby J, Donahue NM, George C, El-Haddad I, Bianchi F, and Riva M
- Subjects
- Monoterpenes chemistry, Nitrates chemistry, Aerosols analysis, Air Pollutants, Volatile Organic Compounds chemistry, Ozone, Bicyclic Monoterpenes
- Abstract
Highly oxygenated organic molecules (HOMs) are a major source of new particles that affect the Earth's climate. HOM production from the oxidation of volatile organic compounds (VOCs) occurs during both the day and night and can lead to new particle formation (NPF). However, NPF involving organic vapors has been reported much more often during the daytime than during nighttime. Here, we show that the nitrate radicals (NO
3 ), which arise predominantly at night, inhibit NPF during the oxidation of monoterpenes based on three lines of observational evidence: NPF experiments in the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN (European Organization for Nuclear Research), radical chemistry experiments using an oxidation flow reactor, and field observations in a wetland that occasionally exhibits nocturnal NPF. Nitrooxy-peroxy radicals formed from NO3 chemistry suppress the production of ultralow-volatility organic compounds (ULVOCs) responsible for biogenic NPF, which are covalently bound peroxy radical (RO2 ) dimer association products. The ULVOC yield of α-pinene in the presence of NO3 is one-fifth of that resulting from ozone chemistry alone. Even trace amounts of NO3 radicals, at sub-parts per trillion level, suppress the NPF rate by a factor of 4. Ambient observations further confirm that when NO3 chemistry is involved, monoterpene NPF is completely turned off. Our results explain the frequent absence of nocturnal biogenic NPF in monoterpene (α-pinene)-rich environments.- Published
- 2024
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272. Iodine oxoacids enhance nucleation of sulfuric acid particles in the atmosphere.
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He XC, Simon M, Iyer S, Xie HB, Rörup B, Shen J, Finkenzeller H, Stolzenburg D, Zhang R, Baccarini A, Tham YJ, Wang M, Amanatidis S, Piedehierro AA, Amorim A, Baalbaki R, Brasseur Z, Caudillo L, Chu B, Dada L, Duplissy J, El Haddad I, Flagan RC, Granzin M, Hansel A, Heinritzi M, Hofbauer V, Jokinen T, Kemppainen D, Kong W, Krechmer J, Kürten A, Lamkaddam H, Lopez B, Ma F, Mahfouz NGA, Makhmutov V, Manninen HE, Marie G, Marten R, Massabò D, Mauldin RL, Mentler B, Onnela A, Petäjä T, Pfeifer J, Philippov M, Ranjithkumar A, Rissanen MP, Schobesberger S, Scholz W, Schulze B, Surdu M, Thakur RC, Tomé A, Wagner AC, Wang D, Wang Y, Weber SK, Welti A, Winkler PM, Zauner-Wieczorek M, Baltensperger U, Curtius J, Kurtén T, Worsnop DR, Volkamer R, Lehtipalo K, Kirkby J, Donahue NM, Sipilä M, and Kulmala M
- Abstract
The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H
2 SO4 ), stabilized by ammonia (NH3 ). However, in marine and polar regions, NH3 is generally low, and H2 SO4 is frequently found together with iodine oxoacids [HIOx , i.e., iodic acid (HIO3 ) and iodous acid (HIO2 )]. In experiments performed with the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated the interplay of H2 SO4 and HIOx during atmospheric particle nucleation. We found that HIOx greatly enhances H2 SO4 (-NH3 ) nucleation through two different interactions. First, HIO3 strongly binds with H2 SO4 in charged clusters so they drive particle nucleation synergistically. Second, HIO2 substitutes for NH3 , forming strongly bound H2 SO4 -HIO2 acid-base pairs in molecular clusters. Global observations imply that HIOx is enhancing H2 SO4 (-NH3 ) nucleation rates 10- to 10,000-fold in marine and polar regions.- Published
- 2023
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273. Intra-arterial vasodilators infusion for management of reversible cerebral vasoconstriction syndrome in a 12-year-old girl: A case report.
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Rizzati F, Marie G, Chanez V, Ferry T, Natterer J, Longchamp D, Saliou G, and Perez MH
- Abstract
Reversible cerebral vasoconstriction syndrome (RCVS) is a vascular disease characterized by diffuse transient vasoconstriction and vasodilatation of the cerebral arteries. It is commonly associated with recurrent severe acute headaches with or without focal neurological deficits due to hemorrhages, infarcts, and even posterior reversible encephalopathy syndrome. The optimal management of acute neurologic deficits caused by RCVS is still uncertain. Calcium channel blockers (CCBs) such as nimodipine or verapamil have been reported to be effective in adult series. Intra-arterial injection of nimodipine, verapamil, and milrinone has recently been demonstrated to be safe and effective for treating severe segmental vasoconstriction in adults. CCBs are the most used treatment in the available pediatric literature. Intra-arterial vasodilators have been reported in some rare pediatric reports with more severe diseases, but their utility is still under investigation. We report a case of a 12-year-old girl who underwent a severe course of RCVS complicated by multiple cerebral infarcts, treated by several sessions of intra-arterial vasodilators infusion., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Rizzati, Marie, Chanez, Ferry, Natterer, Longchamp, Saliou and Perez.)
- Published
- 2023
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274. Molecular Understanding of the Enhancement in Organic Aerosol Mass at High Relative Humidity.
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Surdu M, Lamkaddam H, Wang DS, Bell DM, Xiao M, Lee CP, Li D, Caudillo L, Marie G, Scholz W, Wang M, Lopez B, Piedehierro AA, Ataei F, Baalbaki R, Bertozzi B, Bogert P, Brasseur Z, Dada L, Duplissy J, Finkenzeller H, He XC, Höhler K, Korhonen K, Krechmer JE, Lehtipalo K, Mahfouz NGA, Manninen HE, Marten R, Massabò D, Mauldin R, Petäjä T, Pfeifer J, Philippov M, Rörup B, Simon M, Shen J, Umo NS, Vogel F, Weber SK, Zauner-Wieczorek M, Volkamer R, Saathoff H, Möhler O, Kirkby J, Worsnop DR, Kulmala M, Stratmann F, Hansel A, Curtius J, Welti A, Riva M, Donahue NM, Baltensperger U, and El Haddad I
- Subjects
- Humidity, Aerosols, Monoterpenes chemistry, Air Pollutants
- Abstract
The mechanistic pathway by which high relative humidity (RH) affects gas-particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at high RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a mechanistic understanding of the effect of RH on the partitioning of biogenic oxidized organic molecules (from α-pinene and isoprene) at low temperatures (243 and 263 K) at the CLOUD chamber at CERN. We observe increases in SOA mass of 45 and 85% with increasing RH from 10-20 to 60-80% at 243 and 263 K, respectively, and attribute it to the increased partitioning of semi-volatile compounds. At 263 K, we measure an increase of a factor 2-4 in the concentration of C
10 H16 O2-3 , while the particle-phase concentrations of low-volatility species, such as C10 H16 O6-8 , remain almost constant. This results in a substantial shift in the chemical composition and volatility distribution toward less oxygenated and more volatile species at higher RH (e.g., at 263 K, O/C ratio = 0.55 and 0.40, at RH = 10 and 80%, respectively). By modeling particle growth using an aerosol growth model, which accounts for kinetic limitations, we can explain the enhancement in the semi-volatile fraction through the complementary effect of decreased compound activity and increased bulk-phase diffusivity. Our results highlight the importance of particle water content as a diluting agent and a plasticizer for organic aerosol growth.- Published
- 2023
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275. Effect of medical staff training on vaccination coverage in outpatients with cancer: An interventional multicenter before-and-after study.
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Rivière P, Penel N, Faure K, Marie G, Najem A, Rivière MK, and Panaget S
- Abstract
Purpose: Despite widely disseminated guidelines, pneumococcal and influenza vaccination coverage (VC) remains insufficient in patients with cancer receiving cancer treatment. We performed an interventional study to evaluate VC in patients with cancer treated at the medical oncology departments of three North-of-France hospitals and to assess the effect of medical staff training on VC in these patients., Methods: A standardized questionnaire assessed VC in adult patients with cancer receiving anticancer treatment at three day hospitals during December 2-7, 2019. Subsequently (January 2020), we organized educational training sessions for medical staff from each hospital to discuss the current vaccination guidelines. To assess the impact of training on pneumococcal and influenza VC, we re-administered the same questionnaire in March 2020. Because there are no specific guidelines on Diphtheria-Tetanus-Pertussis (DTP) vaccination and no improvement was expected, DTP VC acted as an internal control., Results: In total, 272 patients from all three hospitals were enrolled in the "before study"; 156 patients from only two hospitals were enrolled in the "after study" as medical training and data collection at the third were impossible because of administrative reasons and COVID-19 pandemic. The predictors were age for DTP VC; treatment center for pneumococcal VC; and age, sex, and tumor histology (adenocarcinoma vs. others) for influenza VC. Neither influenza VC (42.6% vs. 55.1%, p = 0.08), nor pneumococcal VC were significantly improved post-intervention (11.8% vs. 15.4%, p = 1). There seems to be a small effect in the most fragile for influenza VC., Conclusion: As expected, VC was very low in patients with cancer, consistent with the literature. There was no impact of the intervention for pneumococcal and influenza VC., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)
- Published
- 2023
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276. Towards Automated Brain Aneurysm Detection in TOF-MRA: Open Data, Weak Labels, and Anatomical Knowledge.
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Di Noto T, Marie G, Tourbier S, Alemán-Gómez Y, Esteban O, Saliou G, Cuadra MB, Hagmann P, and Richiardi J
- Subjects
- Female, Humans, Magnetic Resonance Angiography methods, Sensitivity and Specificity, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm pathology
- Abstract
Brain aneurysm detection in Time-Of-Flight Magnetic Resonance Angiography (TOF-MRA) has undergone drastic improvements with the advent of Deep Learning (DL). However, performances of supervised DL models heavily rely on the quantity of labeled samples, which are extremely costly to obtain. Here, we present a DL model for aneurysm detection that overcomes the issue with "weak" labels: oversized annotations which are considerably faster to create. Our weak labels resulted to be four times faster to generate than their voxel-wise counterparts. In addition, our model leverages prior anatomical knowledge by focusing only on plausible locations for aneurysm occurrence. We first train and evaluate our model through cross-validation on an in-house TOF-MRA dataset comprising 284 subjects (170 females / 127 healthy controls / 157 patients with 198 aneurysms). On this dataset, our best model achieved a sensitivity of 83%, with False Positive (FP) rate of 0.8 per patient. To assess model generalizability, we then participated in a challenge for aneurysm detection with TOF-MRA data (93 patients, 20 controls, 125 aneurysms). On the public challenge, sensitivity was 68% (FP rate = 2.5), ranking 4th/18 on the open leaderboard. We found no significant difference in sensitivity between aneurysm risk-of-rupture groups (p = 0.75), locations (p = 0.72), or sizes (p = 0.15). Data, code and model weights are released under permissive licenses. We demonstrate that weak labels and anatomical knowledge can alleviate the necessity for prohibitively expensive voxel-wise annotations., (© 2022. The Author(s).)
- Published
- 2023
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277. The gas-phase formation mechanism of iodic acid as an atmospheric aerosol source.
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Finkenzeller H, Iyer S, He XC, Simon M, Koenig TK, Lee CF, Valiev R, Hofbauer V, Amorim A, Baalbaki R, Baccarini A, Beck L, Bell DM, Caudillo L, Chen D, Chiu R, Chu B, Dada L, Duplissy J, Heinritzi M, Kemppainen D, Kim C, Krechmer J, Kürten A, Kvashnin A, Lamkaddam H, Lee CP, Lehtipalo K, Li Z, Makhmutov V, Manninen HE, Marie G, Marten R, Mauldin RL, Mentler B, Müller T, Petäjä T, Philippov M, Ranjithkumar A, Rörup B, Shen J, Stolzenburg D, Tauber C, Tham YJ, Tomé A, Vazquez-Pufleau M, Wagner AC, Wang DS, Wang M, Wang Y, Weber SK, Nie W, Wu Y, Xiao M, Ye Q, Zauner-Wieczorek M, Hansel A, Baltensperger U, Brioude J, Curtius J, Donahue NM, Haddad IE, Flagan RC, Kulmala M, Kirkby J, Sipilä M, Worsnop DR, Kurten T, Rissanen M, and Volkamer R
- Subjects
- Aerosols, Iodates, Iodine
- Abstract
Iodine is a reactive trace element in atmospheric chemistry that destroys ozone and nucleates particles. Iodine emissions have tripled since 1950 and are projected to keep increasing with rising O
3 surface concentrations. Although iodic acid (HIO3 ) is widespread and forms particles more efficiently than sulfuric acid, its gas-phase formation mechanism remains unresolved. Here, in CLOUD atmospheric simulation chamber experiments that generate iodine radicals at atmospherically relevant rates, we show that iodooxy hypoiodite, IOIO, is efficiently converted into HIO3 via reactions (R1) IOIO + O3 → IOIO4 and (R2) IOIO4 + H2 O → HIO3 + HOI +(1) O2 . The laboratory-derived reaction rate coefficients are corroborated by theory and shown to explain field observations of daytime HIO3 in the remote lower free troposphere. The mechanism provides a missing link between iodine sources and particle formation. Because particulate iodate is readily reduced, recycling iodine back into the gas phase, our results suggest a catalytic role of iodine in aerosol formation., (© 2022. The Author(s).)- Published
- 2023
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278. High Gas-Phase Methanesulfonic Acid Production in the OH-Initiated Oxidation of Dimethyl Sulfide at Low Temperatures.
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Shen J, Scholz W, He XC, Zhou P, Marie G, Wang M, Marten R, Surdu M, Rörup B, Baalbaki R, Amorim A, Ataei F, Bell DM, Bertozzi B, Brasseur Z, Caudillo L, Chen D, Chu B, Dada L, Duplissy J, Finkenzeller H, Granzin M, Guida R, Heinritzi M, Hofbauer V, Iyer S, Kemppainen D, Kong W, Krechmer JE, Kürten A, Lamkaddam H, Lee CP, Lopez B, Mahfouz NGA, Manninen HE, Massabò D, Mauldin RL, Mentler B, Müller T, Pfeifer J, Philippov M, Piedehierro AA, Roldin P, Schobesberger S, Simon M, Stolzenburg D, Tham YJ, Tomé A, Umo NS, Wang D, Wang Y, Weber SK, Welti A, Wollesen de Jonge R, Wu Y, Zauner-Wieczorek M, Zust F, Baltensperger U, Curtius J, Flagan RC, Hansel A, Möhler O, Petäjä T, Volkamer R, Kulmala M, Lehtipalo K, Rissanen M, Kirkby J, El-Haddad I, Bianchi F, Sipilä M, Donahue NM, and Worsnop DR
- Abstract
Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric acid, H
2 SO4 ). Despite their importance, accurate prediction of MSA and H2 SO4 from DMS oxidation remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, we show that decreasing the temperature from +25 to -10 °C enhances the gas-phase MSA production by an order of magnitude from OH-initiated DMS oxidation, while H2 SO4 production is modestly affected. This leads to a gas-phase H2 SO4 -to-MSA ratio (H2 SO4 /MSA) smaller than one at low temperatures, consistent with field observations in polar regions. With an updated DMS oxidation mechanism, we find that methanesulfinic acid, CH3 S(O)OH, MSIA, forms large amounts of MSA. Overall, our results reveal that MSA yields are a factor of 2-10 higher than those predicted by the widely used Master Chemical Mechanism (MCMv3.3.1), and the NOx effect is less significant than that of temperature. Our updated mechanism explains the high MSA production rates observed in field observations, especially at low temperatures, thus, substantiating the greater importance of MSA in the natural sulfur cycle and natural CCN formation. Our mechanism will improve the interpretation of present-day and historical gas-phase H2 SO4 /MSA measurements.- Published
- 2022
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279. Synergistic HNO 3 -H 2 SO 4 -NH 3 upper tropospheric particle formation.
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Wang M, Xiao M, Bertozzi B, Marie G, Rörup B, Schulze B, Bardakov R, He XC, Shen J, Scholz W, Marten R, Dada L, Baalbaki R, Lopez B, Lamkaddam H, Manninen HE, Amorim A, Ataei F, Bogert P, Brasseur Z, Caudillo L, De Menezes LP, Duplissy J, Ekman AML, Finkenzeller H, Carracedo LG, Granzin M, Guida R, Heinritzi M, Hofbauer V, Höhler K, Korhonen K, Krechmer JE, Kürten A, Lehtipalo K, Mahfouz NGA, Makhmutov V, Massabò D, Mathot S, Mauldin RL, Mentler B, Müller T, Onnela A, Petäjä T, Philippov M, Piedehierro AA, Pozzer A, Ranjithkumar A, Schervish M, Schobesberger S, Simon M, Stozhkov Y, Tomé A, Umo NS, Vogel F, Wagner R, Wang DS, Weber SK, Welti A, Wu Y, Zauner-Wieczorek M, Sipilä M, Winkler PM, Hansel A, Baltensperger U, Kulmala M, Flagan RC, Curtius J, Riipinen I, Gordon H, Lelieveld J, El-Haddad I, Volkamer R, Worsnop DR, Christoudias T, Kirkby J, Möhler O, and Donahue NM
- Abstract
New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)
1-4 . However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components. The importance of this mechanism depends on the availability of ammonia, which was previously thought to be efficiently scavenged by cloud droplets during convection. However, surprisingly high concentrations of ammonia and ammonium nitrate have recently been observed in the upper troposphere over the Asian monsoon region5,6 . Once particles have formed, co-condensation of ammonia and abundant nitric acid alone is sufficient to drive rapid growth to CCN sizes with only trace sulfate. Moreover, our measurements show that these CCN are also highly efficient ice nucleating particles-comparable to desert dust. Our model simulations confirm that ammonia is efficiently convected aloft during the Asian monsoon, driving rapid, multi-acid HNO3 -H2 SO4 -NH3 nucleation in the upper troposphere and producing ice nucleating particles that spread across the mid-latitude Northern Hemisphere., (© 2022. The Author(s).)- Published
- 2022
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280. Survival of newly formed particles in haze conditions.
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Marten R, Xiao M, Rörup B, Wang M, Kong W, He XC, Stolzenburg D, Pfeifer J, Marie G, Wang DS, Scholz W, Baccarini A, Lee CP, Amorim A, Baalbaki R, Bell DM, Bertozzi B, Caudillo L, Chu B, Dada L, Duplissy J, Finkenzeller H, Carracedo LG, Granzin M, Hansel A, Heinritzi M, Hofbauer V, Kemppainen D, Kürten A, Lampimäki M, Lehtipalo K, Makhmutov V, Manninen HE, Mentler B, Petäjä T, Philippov M, Shen J, Simon M, Stozhkov Y, Tomé A, Wagner AC, Wang Y, Weber SK, Wu Y, Zauner-Wieczorek M, Curtius J, Kulmala M, Möhler O, Volkamer R, Winkler PM, Worsnop DR, Dommen J, Flagan RC, Kirkby J, Donahue NM, Lamkaddam H, Baltensperger U, and El Haddad I
- Abstract
Intense new particle formation events are regularly observed under highly polluted conditions, despite the high loss rates of nucleated clusters. Higher than expected cluster survival probability implies either ineffective scavenging by pre-existing particles or missing growth mechanisms. Here we present experiments performed in the CLOUD chamber at CERN showing particle formation from a mixture of anthropogenic vapours, under condensation sinks typical of haze conditions, up to 0.1 s
-1 . We find that new particle formation rates substantially decrease at higher concentrations of pre-existing particles, demonstrating experimentally for the first time that molecular clusters are efficiently scavenged by larger sized particles. Additionally, we demonstrate that in the presence of supersaturated gas-phase nitric acid (HNO3 ) and ammonia (NH3 ), freshly nucleated particles can grow extremely rapidly, maintaining a high particle number concentration, even in the presence of a high condensation sink. Such high growth rates may explain the high survival probability of freshly formed particles under haze conditions. We identify under what typical urban conditions HNO3 and NH3 can be expected to contribute to particle survival during haze., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2022
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281. Comparing methods of detecting and segmenting unruptured intracranial aneurysms on TOF-MRAS: The ADAM challenge.
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Timmins KM, van der Schaaf IC, Bennink E, Ruigrok YM, An X, Baumgartner M, Bourdon P, De Feo R, Noto TD, Dubost F, Fava-Sanches A, Feng X, Giroud C, Group I, Hu M, Jaeger PF, Kaiponen J, Klimont M, Li Y, Li H, Lin Y, Loehr T, Ma J, Maier-Hein KH, Marie G, Menze B, Richiardi J, Rjiba S, Shah D, Shit S, Tohka J, Urruty T, Walińska U, Yang X, Yang Y, Yin Y, Velthuis BK, and Kuijf HJ
- Subjects
- Datasets as Topic, Educational Measurement, Humans, Magnetic Resonance Imaging, Random Allocation, Risk Assessment, Cerebral Angiography methods, Intracranial Aneurysm diagnostic imaging, Magnetic Resonance Angiography methods
- Abstract
Accurate detection and quantification of unruptured intracranial aneurysms (UIAs) is important for rupture risk assessment and to allow an informed treatment decision to be made. Currently, 2D manual measures used to assess UIAs on Time-of-Flight magnetic resonance angiographies (TOF-MRAs) lack 3D information and there is substantial inter-observer variability for both aneurysm detection and assessment of aneurysm size and growth. 3D measures could be helpful to improve aneurysm detection and quantification but are time-consuming and would therefore benefit from a reliable automatic UIA detection and segmentation method. The Aneurysm Detection and segMentation (ADAM) challenge was organised in which methods for automatic UIA detection and segmentation were developed and submitted to be evaluated on a diverse clinical TOF-MRA dataset. A training set (113 cases with a total of 129 UIAs) was released, each case including a TOF-MRA, a structural MR image (T1, T2 or FLAIR), annotation of any present UIA(s) and the centre voxel of the UIA(s). A test set of 141 cases (with 153 UIAs) was used for evaluation. Two tasks were proposed: (1) detection and (2) segmentation of UIAs on TOF-MRAs. Teams developed and submitted containerised methods to be evaluated on the test set. Task 1 was evaluated using metrics of sensitivity and false positive count. Task 2 was evaluated using dice similarity coefficient, modified hausdorff distance (95
th percentile) and volumetric similarity. For each task, a ranking was made based on the average of the metrics. In total, eleven teams participated in task 1 and nine of those teams participated in task 2. Task 1 was won by a method specifically designed for the detection task (i.e. not participating in task 2). Based on segmentation metrics, the top two methods for task 2 performed statistically significantly better than all other methods. The detection performance of the top-ranking methods was comparable to visual inspection for larger aneurysms. Segmentation performance of the top ranking method, after selection of true UIAs, was similar to interobserver performance. The ADAM challenge remains open for future submissions and improved submissions, with a live leaderboard to provide benchmarking for method developments at https://adam.isi.uu.nl/., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2021
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282. Role of iodine oxoacids in atmospheric aerosol nucleation.
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He XC, Tham YJ, Dada L, Wang M, Finkenzeller H, Stolzenburg D, Iyer S, Simon M, Kürten A, Shen J, Rörup B, Rissanen M, Schobesberger S, Baalbaki R, Wang DS, Koenig TK, Jokinen T, Sarnela N, Beck LJ, Almeida J, Amanatidis S, Amorim A, Ataei F, Baccarini A, Bertozzi B, Bianchi F, Brilke S, Caudillo L, Chen D, Chiu R, Chu B, Dias A, Ding A, Dommen J, Duplissy J, El Haddad I, Gonzalez Carracedo L, Granzin M, Hansel A, Heinritzi M, Hofbauer V, Junninen H, Kangasluoma J, Kemppainen D, Kim C, Kong W, Krechmer JE, Kvashin A, Laitinen T, Lamkaddam H, Lee CP, Lehtipalo K, Leiminger M, Li Z, Makhmutov V, Manninen HE, Marie G, Marten R, Mathot S, Mauldin RL, Mentler B, Möhler O, Müller T, Nie W, Onnela A, Petäjä T, Pfeifer J, Philippov M, Ranjithkumar A, Saiz-Lopez A, Salma I, Scholz W, Schuchmann S, Schulze B, Steiner G, Stozhkov Y, Tauber C, Tomé A, Thakur RC, Väisänen O, Vazquez-Pufleau M, Wagner AC, Wang Y, Weber SK, Winkler PM, Wu Y, Xiao M, Yan C, Ye Q, Ylisirniö A, Zauner-Wieczorek M, Zha Q, Zhou P, Flagan RC, Curtius J, Baltensperger U, Kulmala M, Kerminen VM, Kurtén T, Donahue NM, Volkamer R, Kirkby J, Worsnop DR, and Sipilä M
- Abstract
Iodic acid (HIO
3 ) is known to form aerosol particles in coastal marine regions, but predicted nucleation and growth rates are lacking. Using the CERN CLOUD (Cosmics Leaving Outdoor Droplets) chamber, we find that the nucleation rates of HIO3 particles are rapid, even exceeding sulfuric acid-ammonia rates under similar conditions. We also find that ion-induced nucleation involves IO3 - and the sequential addition of HIO3 and that it proceeds at the kinetic limit below +10°C. In contrast, neutral nucleation involves the repeated sequential addition of iodous acid (HIO2 ) followed by HIO3 , showing that HIO2 plays a key stabilizing role. Freshly formed particles are composed almost entirely of HIO3 , which drives rapid particle growth at the kinetic limit. Our measurements indicate that iodine oxoacid particle formation can compete with sulfuric acid in pristine regions of the atmosphere., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)- Published
- 2021
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283. Staphylococcus aureus mediastinitis due to subclavian vein perforation and catheter-related-infection.
- Author
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Rivière P, Bauer J, Hégo F, Raad N, Najem A, Tomaszewski A, Dandoy S, and Marie G
- Abstract
In rare cases the implantation or use of a port-a-cath can be complicated by venous perforation or catheter-related infection. We describe a patient with these two complications resulting in Staphylococcus aureus mediastinitis. Removal of the device and prolonged antibiotic therapy cured the infection., Competing Interests: The authors declare that they have no conflict of interest., (© 2020 The Author(s).)
- Published
- 2021
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284. Discriminating cognitive motor dissociation from disorders of consciousness using structural MRI.
- Author
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Pozeg P, Jöhr J, Pincherle A, Marie G, Ryvlin P, Meuli R, Hagmann P, Diserens K, and Dunet V
- Subjects
- Brain diagnostic imaging, Consciousness Disorders diagnostic imaging, Humans, Neuroimaging, Consciousness, Magnetic Resonance Imaging
- Abstract
An accurate evaluation and detection of awareness after a severe brain injury is crucial to a patient's diagnosis, therapy, and end-of-life decisions. Misdiagnosis is frequent as behavior-based assessments often overlook subtle signs of consciousness. This study aimed to identify brain MRI characteristics of patients with residual consciousness after a severe brain injury and to develop a simple MRI-based scoring system according to the findings. We retrieved data from 128 patients and split them into a development or validation set. Structural brain MRIs were qualitatively assessed for lesions in 18 brain regions. We used logistic regression and support vector machine algorithms to first identify the most relevant brain regions predicting a patient's outcome in the development set. We next built a diagnostic MRI-based score and estimated its optimal diagnostic cut-off point. The classifiers were then tested on the validation set and their performance compared using the receiver operating characteristic curve. Relevant brain regions predicting negative outcome highly overlapped between both classifiers and included the left mesencephalon, right basal ganglia, right thalamus, right parietal cortex, and left frontal cortex. The support vector machine classifier showed higher accuracy (0.93, 95% CI: 0.81-0.96) and specificity (0.97, 95% CI: 0.85-1) than logistic regression (accuracy: 0.87, 95% CI: 0.73 - 0.95; specificity: 0.90, 95% CI: 0.75-0.97), but equal sensitivity (0.67, 95% CI: 0.24-0.94 and 0.22-0.96, respectively) for distinguishing patients with and without residual consciousness. The novel MRI-based score assessing brain lesions in patients with disorders of consciousness accurately detects patients with residual consciousness. It could complement valuably behavioral evaluation as it is time-efficient and requires only conventional MRI., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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- View/download PDF
285. Rapid growth of new atmospheric particles by nitric acid and ammonia condensation.
- Author
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Wang M, Kong W, Marten R, He XC, Chen D, Pfeifer J, Heitto A, Kontkanen J, Dada L, Kürten A, Yli-Juuti T, Manninen HE, Amanatidis S, Amorim A, Baalbaki R, Baccarini A, Bell DM, Bertozzi B, Bräkling S, Brilke S, Murillo LC, Chiu R, Chu B, De Menezes LP, Duplissy J, Finkenzeller H, Carracedo LG, Granzin M, Guida R, Hansel A, Hofbauer V, Krechmer J, Lehtipalo K, Lamkaddam H, Lampimäki M, Lee CP, Makhmutov V, Marie G, Mathot S, Mauldin RL, Mentler B, Müller T, Onnela A, Partoll E, Petäjä T, Philippov M, Pospisilova V, Ranjithkumar A, Rissanen M, Rörup B, Scholz W, Shen J, Simon M, Sipilä M, Steiner G, Stolzenburg D, Tham YJ, Tomé A, Wagner AC, Wang DS, Wang Y, Weber SK, Winkler PM, Wlasits PJ, Wu Y, Xiao M, Ye Q, Zauner-Wieczorek M, Zhou X, Volkamer R, Riipinen I, Dommen J, Curtius J, Baltensperger U, Kulmala M, Worsnop DR, Kirkby J, Seinfeld JH, El-Haddad I, Flagan RC, and Donahue NM
- Abstract
A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog
1,2 , but how it occurs in cities is often puzzling3 . If the growth rates of urban particles are similar to those found in cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below -15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acid-base stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms4,5 .- Published
- 2020
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286. Spatiotemporal Pattern of Gadodiamide-Related T1 Hyperintensity Increase Within the Deep Brain Nuclei.
- Author
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Marie GPO, Pozeg P, Meuli RA, Maeder P, and Forget J
- Subjects
- Adult, Aged, Brain Mapping statistics & numerical data, Female, Humans, Linear Models, Longitudinal Studies, Magnetic Resonance Imaging statistics & numerical data, Male, Middle Aged, Retrospective Studies, Brain diagnostic imaging, Brain Mapping methods, Contrast Media pharmacokinetics, Gadolinium DTPA pharmacokinetics, Image Enhancement methods, Magnetic Resonance Imaging methods
- Abstract
Objectives: The purpose of the study was to systematically evaluate the precise spatial and temporal pattern of gadolinium-related changes in T1-weighted signal intensity on unenhanced magnetic resonance (MR) images, occurring in the deep brain nuclei of adult patients exposed to at least 10 consecutive doses of gadodiamide., Materials and Methods: In this monocentric retrospective longitudinal study, we analyzed the brain MR images of 30 patients (12 women, 18 men; mean age, 43 ± 11.6 years) acquired between December 1998 and March 2008. We drew the regions of interest in the dentate nucleus, globus pallidus, putamen, pulvinar, ventral posterior nucleus of the thalamus, superior colliculus, substantia nigra, and white matter on unenhanced T1-weighted images. Each region of interest's mean signal intensity was normalized by the mean intensity of the pons. The normalized signal intensities were measured at the baseline before first gadodiamide administration and at each of 10 successive MR imaging examinations. We used linear mixed effects models to analyze the data., Results: We observed a significant linear increase of signal intensity ratios across 10 successive gadodiamide administrations (all basal nuclei were significant at P < 0.001, except the ventral posterior thalamus, where P < 0.05), with the fastest signal intensity increase in the dentate nucleus (B = 0.010), followed by the globus pallidus (B = 0.0068), putamen (B = 0.0063), pulvinar (B = 0.0062), superior colliculus (B = 0.0057), substantia nigra (B = 0.0034), and ventral posterior nucleus of the thalamus (B = 0.0031). No significant signal increase was observed in the white matter (P > 0.05)., Conclusions: Multiple consecutive administration of gadodiamide is associated with an increase in T1-weighted hypersignal on the unenhanced scans, displaying a gradual and nonuniform pattern across different deep brain nuclei, including the ventral posterior thalamus, which was used as a reference tissue in previous studies.
- Published
- 2018
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287. Proof of concept of wastewater treatment via passive aeration SND using a novel zeolite amended biofilm reactor.
- Author
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Cheng L, Flavigny RM, Hossain MI, Charles W, and Cord-Ruwisch R
- Subjects
- Nitrogen, Sewage, Wastewater, Zeolites, Biofilms, Bioreactors, Waste Disposal, Fluid methods
- Abstract
The current paper describes a novel passive aeration simultaneous nitrification and denitrification (PASND) zeolite amended biofilm reactor that removes organic carbon and nitrogen from wastewater with low-energy consumption. Next to the ammonium oxidizing bacteria (AOB), this reactor contained naturally enriched glycogen accumulating organisms (GAOs) and zeolite powder to initially adsorb BOD (acetate) and ammonium (NH
4 + -N) from synthetic wastewater under anaerobic conditions. Draining of the treated wastewater exposed the biofilm directly to air enabling low-energy oxygen supply by passive aeration. This allowed the adsorbed ammonium to be oxidized by the AOB and the produced nitrite and nitrate to be reduced simultaneously by the GAOs using the adsorbed BOD (stored as PHAs) as carbon source. Overall, with an operation mode of 1 h anaerobic and 4 h aerobic phase, the nutrient removal efficiency after single treatment was about 94.3% for BOD and 72.2% for nitrogen (NH4 + -N). As high-energy aeration of the bulk solution for oxygen supply is completely avoided, the energy requirement of the proposed PASND biofilm reactor can be theoretically cut down to more than 50% compared to the traditional activated sludge process.- Published
- 2018
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288. Trade-offs in using European forests to meet climate objectives.
- Author
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Luyssaert S, Marie G, Valade A, Chen YY, Njakou Djomo S, Ryder J, Otto J, Naudts K, Lansø AS, Ghattas J, and McGrath MJ
- Subjects
- Air, Atmosphere chemistry, Carbon Dioxide analysis, Europe, Geographic Mapping, International Cooperation, Temperature, Carbon Sequestration, Forestry, Forests, Global Warming legislation & jurisprudence, Global Warming prevention & control, Goals, Sustainable Development legislation & jurisprudence
- Abstract
The Paris Agreement promotes forest management as a pathway towards halting climate warming through the reduction of carbon dioxide (CO
2 ) emissions1 . However, the climate benefits from carbon sequestration through forest management may be reinforced, counteracted or even offset by concurrent management-induced changes in surface albedo, land-surface roughness, emissions of biogenic volatile organic compounds, transpiration and sensible heat flux2-4 . Consequently, forest management could offset CO2 emissions without halting global temperature rise. It therefore remains to be confirmed whether commonly proposed sustainable European forest-management portfolios would comply with the Paris Agreement-that is, whether they can reduce the growth rate of atmospheric CO2 , reduce the radiative imbalance at the top of the atmosphere, and neither increase the near-surface air temperature nor decrease precipitation by the end of the twenty-first century. Here we show that the portfolio made up of management systems that locally maximize the carbon sink through carbon sequestration, wood use and product and energy substitution reduces the growth rate of atmospheric CO2 , but does not meet any of the other criteria. The portfolios that maximize the carbon sink or forest albedo pass only one-different in each case-criterion. Managing the European forests with the objective of reducing near-surface air temperature, on the other hand, will also reduce the atmospheric CO2 growth rate, thus meeting two of the four criteria. Trade-off are thus unavoidable when using European forests to meet climate objectives. Furthermore, our results demonstrate that if present-day forest cover is sustained, the additional climate benefits achieved through forest management would be modest and local, rather than global. On the basis of these findings, we argue that Europe should not rely on forest management to mitigate climate change. The modest climate effects from changes in forest management imply, however, that if adaptation to future climate were to require large-scale changes in species composition and silvicultural systems over Europe5,6 , the forests could be adapted to climate change with neither positive nor negative climate effects.- Published
- 2018
- Full Text
- View/download PDF
289. Digitization of multistep organic synthesis in reactionware for on-demand pharmaceuticals.
- Author
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Kitson PJ, Marie G, Francoia JP, Zalesskiy SS, Sigerson RC, Mathieson JS, and Cronin L
- Subjects
- Baclofen chemical synthesis, GABA-B Receptor Agonists chemical synthesis, Plastics, Chemistry Techniques, Synthetic instrumentation, Chemistry Techniques, Synthetic methods, Pharmaceutical Preparations chemical synthesis, Printing, Three-Dimensional
- Abstract
Chemical manufacturing is often done at large facilities that require a sizable capital investment and then produce key compounds for a finite period. We present an approach to the manufacturing of fine chemicals and pharmaceuticals in a self-contained plastic reactionware device. The device was designed and constructed by using a chemical to computer-automated design (ChemCAD) approach that enables the translation of traditional bench-scale synthesis into a platform-independent digital code. This in turn guides production of a three-dimensional printed device that encloses the entire synthetic route internally via simple operations. We demonstrate the approach for the γ-aminobutyric acid receptor agonist, (±)-baclofen, establishing a concept that paves the way for the local manufacture of drugs outside of specialist facilities., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
- Published
- 2018
- Full Text
- View/download PDF
290. Organic carbon removal from wastewater by a PHA storing biofilm using direct atmospheric air contact as oxygen supply.
- Author
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Flavigny RM and Cord-Ruwisch R
- Subjects
- Atmosphere chemistry, Carbon isolation & purification, Organic Chemicals isolation & purification, Organic Chemicals metabolism, Sewage microbiology, Wastewater chemistry, Water Pollutants, Chemical isolation & purification, Water Pollutants, Chemical metabolism, Biofilms growth & development, Carbon metabolism, Oxygen metabolism, Polyhydroxyalkanoates chemistry, Wastewater microbiology, Water Purification methods
- Abstract
The principal reason for the high energy costs for biological wastewater treatment is the poor transfer efficiency of oxygen to the bulk water phase. The current paper describes a biofilm reactor in which oxygen transfer to the bulk solution is avoided by alternating anaerobic submersed (2h) and drained (1h) operation of the biofilm. During the submersed phase the biofilm enriched for glycogen accumulating organism (GAO) stored the organic carbon (acetate) as poly-hydroxy-alkanoate (PHA). After draining the reactor, this carbon stored as PHA was biologically oxidised, using oxygen directly from the atmosphere. The 12Cmmol/L (384mg/L BOD) of acetate was completely removed during long term automated operation of the reactor for 9months with a cycle length of 3.3h. As the process specifically removes dissolved organic carbon but not N or P it could possibly be coupled with novel processes such as Anammox or nutrient recovery., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
- Full Text
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291. Incubation time, functional litter diversity, and habitat characteristics predict litter-mixing effects on decomposition.
- Author
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Lecerf A, Marie G, Kominoski JS, LeRoy CJ, Bernadet C, and Swan CM
- Subjects
- Biomass, Time Factors, Biodegradation, Environmental, Ecosystem, Plant Leaves, Trees
- Abstract
Plant diversity influences many fundamental ecosystem functions, including carbon and nutrient dynamics, during litter breakdown. Mixing different litter species causes litter mixtures to lose mass at different rates than expected from component species incubated in isolation. Such nonadditive litter-mixing effects on breakdown processes often occur idiosyncratically because their direction and magnitude change with incubation time, litter species composition, and ecosystem characteristics. Taking advantage of results from 18 litter mixture experiments in streams, we examined whether the direction and magnitude of nonadditive mixing effects are randomly determined. Across 171 tested litter mixtures and 510 incubation time-by-mixture combinations, nonadditive effects on breakdown were common and on average resulted in slightly faster decomposition than expected. In addition, we found that the magnitude of nonadditive effects and the relative balance of positive and negative responses in mixtures change predictably over time, and both were related to an index of functional litter diversity and selected environmental characteristics. Based on these, it should be expected that nonadditive effects are stronger for litter mixtures made of functionally dissimilar species especially in smaller streams. Our findings demonstrate that effects of litter diversity on plant mixture breakdown are more predictable than generally thought. We further argue that the consequences of current worldwide homogenization in the composition of plant traits on carbon and nutrient dynamics could be better inferred from long-duration experiments that manipulate both functional litter diversity and ecosystem characteristics in "hotspots of biodiversity effects," such as small streams.
- Published
- 2011
- Full Text
- View/download PDF
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