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1. Comparing hydrothermal sintering and cold sintering process: Mechanisms, microstructure, kinetics and chemistry

Author

Mert Y. Sengul, Catherine Elissalde, Jean Marc Thibaud, Adri C. T. van Duin, Dominique Denux, Kosuke Tsuji, Clive A. Randall, Thomas Hérisson de Beauvoir, Graziella Goglio, Sun Hwi Bang, Kenji Takashima, Arnaud Ndayishimiye, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), TAIYO YUDEN CO. (JAPAN), The Pennsylvania State University - PENNSTATE (USA), Centre Interuniversitaire de Recherche et d'Ingénierie des Matériaux - CIRIMAT (Toulouse, France), Materials Research Institute, Pennsylvania State University (Penn State), Penn State System-Penn State System, Department of Materials Science and Engineering, Penn State System, TAIYO YUDEN CO., LTD., Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Mechanical Engineering, and This work was supported by Murata Manufacturing Co., Ltd (funding 432-43 42MM, A.N.), the National Science Foundation (DMR-1728634) and AFOSR grant (grant no. FA9550-16-1-0429, C.A.R.). A.C.T.vD acknowledges funding support from the Multi-Scale Fluid-Solid Interactions in Architected and Natural Materials (MUSE) Center funded by U.S. Department of Energy (DOE). MYS acknowledges partial funding support from U.S. National Science Foundation under Award No. DMR-1842922. We gratefully acknowledge Dr. Ke Wang (Materials Characterization Laboratory, Penn State University) for TEM analysis and Dr. Marie-Anne Dourges (Institut des Sciences Moléculaires, UMR 5255) for mercury intrusion porosimetry and fruitful discussions.

Subjects
Ceramics, Materials science, Matériaux, Cold sintering, Kinetics, Pellets, Sintering, chemistry.chemical_element, 02 engineering and technology, Zinc, Molecular dynamics, 01 natural sciences, Hydrothermal circulation, [SPI.MAT]Engineering Sciences [physics]/Materials, Hydrothermal sintering, ReaxFF, 0103 physical sciences, Materials Chemistry, Ceramic, 010302 applied physics, 021001 nanoscience & nanotechnology, Microstructure, chemistry, Chemical engineering, visual_art, Ceramics and Composites, visual_art.visual_art_medium, 0210 nano-technology
Abstract

International audience; This study reports the sintering of zinc oxide (ZnO) through the comparison between the hydrothermal sintering (HS) and the cold sintering process (CSP) operating in closed and open conditions, respectively. Sintering was performed at 155 ± 5 °C applying a pressure of 320 MPa, and during different holding times (0 min, 20 min, 40 min and 80 min). Whatever the low sintering process used, ceramics characteristics are almost similar in terms of relative densities and ZnO structure. However, several differences such as the nature of stabilized phases, grain sizes and quantities of residual molecules in the densified pellets, were characterized and explained. The formation of zinc acetate “bridges” was observed ex situ in hydrothermally sintered samples. A detailed ReaxFF molecular dynamics simulation was performed to help understand the formation mechanisms of zinc acetate “bridges” and compare the chemical activities between HS and CSP.

Published
2020

2. Global well-posedness and long-time dynamics for a higher order quasi-geostrophic type equation

Author

Francesco Fanelli, Francesco De Anna, Penn State University Math department (PENN STATE UNIVERSITY), Pennsylvania State University (Penn State), Penn State System-Penn State System, Institut Camille Jordan [Villeurbanne] (ICJ), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Équations aux dérivées partielles, analyse (EDPA), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), Université de Lyon, ANR-10-LABX-0070,MILYON,Community of mathematics and fundamental computer science in Lyon(2010), and ANR-16-CE40-0027,BORDS,Bords, oscillations et couches limites dans les systèmes différentiels(2016)

Subjects
decay estimates, 2010 Mathematics Subject Classication: 35Q35 (primary), 35K25, 35B65, 35B40, 35Q86 (secondary), Mathematics::Analysis of PDEs, Structure (category theory), BD-entropy structure, Space (mathematics), global well-posedness, 01 natural sciences, Quasi-geostrophic equation, Mathematics - Analysis of PDEs, FOS: Mathematics, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], Uniqueness, Limit (mathematics), 0101 mathematics, Remainder, Mathematics, Omega equation, energy estimates, 010102 general mathematics, Mathematical analysis, Zero (complex analysis), long- time behaviour, 010101 applied mathematics, Analysis, Geostrophic wind, Analysis of PDEs (math.AP)
Abstract

In this paper we study a higher order viscous quasi-geostrophic type equation. This equation was derived in [11] as the limit dynamics of a singularly perturbed Navier-Stokes-Korteweg system with Coriolis force, when the Mach, Rossby and Weber numbers go to zero at the same rate. The scope of the present paper is twofold. First of all, we investigate well-posedness of such a model on the whole space $\R^2$: we prove that it is well-posed in $H^s$ for any $s\geq3$, globally in time. Interestingly enough, we show that this equation owns two levels of energy estimates, for which one gets existence and uniqueness of weak solutions with different regularities (namely, $H^3$ and $H^4$ regularities); this fact can be viewed as a remainder of the so called BD-entropy structure of the original system. In the second part of the paper we investigate the long-time behaviour of these solutions. We show that they converge to the solution of the corresponding linear parabolic type equation, with same initial datum and external force. Our proof is based on dispersive estimates both for the solutions to the linear and non-linear problems., Submitted

Published
2018

3. Hydrology and microtopography control carbon dynamics in wetlands: Implications in partitioning ecosystem respiration in a coastal plain forested wetland

Author

Carl C. Trettin, John S. King, Steve McNulty, Asko Noormets, Ge Sun, Jean-Christophe Domec, Montserrat Fuentes, Guofang Miao, Department of Forestry and Environmental Resources, North Carolina State University [Raleigh] (NC State), University of North Carolina System (UNC)-University of North Carolina System (UNC), Department of Natural Resources and Environmental Sciences, University of Illinois System, Department of Ecosystem Science and Management, Pennsylvania State University (Penn State), Penn State System-Penn State System, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Nicholas School of the Environment, Duke University [Durham], North Carolina State University, Center for High Performance Simulation and Department of Chemical and Biomolecular Engineering, and United States Department of Agriculture (USDA)

Subjects
0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, Coastal plain, Water table, [SDV]Life Sciences [q-bio], microtopography, Eddy covariance, hydrology, Wetland, 01 natural sciences, Hydrology (agriculture), eddy covariance flux, Ecosystem, 14. Life underwater, chamber flux, 0105 earth and related environmental sciences, Hydrology, Global and Planetary Change, geography, geography.geographical_feature_category, Forestry, 15. Life on land, Water level, 13. Climate action, [SDE]Environmental Sciences, Environmental science, Ecosystem respiration, forested wetland, Agronomy and Crop Science, respiration, 010606 plant biology & botany
Abstract

International audience; Wetlands store a disproportionately large fraction of organic carbon relative to their areal coverage, and thus play an important role in global climate mitigation. As destabilization of these stores through land use or environmental change represents a significant climate feedback, it is important to understand the functional regulation of respiratory processes that catabolize them. In this study, we established an eddy covariance flux tower project in a coastal plain forested wetland in North Carolina, USA, and measured total ecosystem respiration (R-e) over three years (2009-2011). We evaluated the magnitude and variability of three respiration components-belowground (R-s), coarse woody debris (R-CWD), and aboveground plant (R-asp) respiration at the ecosystem scale, by accounting microtopographic variation for upscaling and constraining the mass balance with R-e. Strong hydrologic control was detected for 12, and R-CWD,, whereas R-asp and R-e were relatively insensitive to water table fluctuations. In a relatively dry year (2010), this forested wetland respired a total of about 2000 g CO2-C m(-2)y(-1) annually, 51% as R-s, 37% as R-agp, and 12% as R-CWD. During non-flooded periods R-s contributed up to 57% of R-e and during flooded periods R-asp contributed up to 69%. The contribution of R-e to R-e increased by 2.4% for every cm of decrease in water level at intermediate water table level, and was nearly constant when flooded or when the water level more than 15 cm below ground. The contrasting sensitivity of different respiration components highlights the need for explicit consideration of this dynamic in ecosystem and Earth System Models.

Published
2017

4. Effects of land-use change and drought on decadal evapotranspiration and water balance of natural and managed forested wetlands along the southeastern US lower coastal plain

Author

Ge Sun, Kevan J. Minick, John S. King, Steve McNulty, Asko Noormets, Maricar Aguilos, Bhaskar Mitra, Michael Gavazzi, Yun Yang, Jean-Christophe Domec, Prajaya Prajapati, North Carolina State University [Raleigh] (NC State), University of North Carolina System (UNC), United States Department of Agriculture (USDA), Texas A&M University System, Interactions Sol Plante Atmosphère (UMR ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Eastern Forest Environmental Threat Assessment Center, Forest Service, Department of Ecosystem Science and Management, Pennsylvania State University (Penn State), Penn State System-Penn State System, and Texas A&M University [College Station]

Subjects
0106 biological sciences, Canopy, Atmospheric Science, 010504 meteorology & atmospheric sciences, Coastal plain, Chronosequence, Coastal plain forest, Eddy covariance, Wetland, 01 natural sciences, Water balance, Hydrology (agriculture), Evapotranspiration, 0105 earth and related environmental sciences, Forested wetlands, Global and Planetary Change, geography, geography.geographical_feature_category, Managed forests, Drought, Forestry, 15. Life on land, 13. Climate action, [SDE]Environmental Sciences, Environmental science, Agronomy and Crop Science, 010606 plant biology & botany
Abstract

International audience; Forested wetlands are important in regulating regional hydrology and climate. However, long-term studies on the hydrologic impacts of converting natural forested wetlands to pine plantations are rare for the southern US. From 2005-2018, we quantified water cycling in two post-harvest and newly-planted loblolly pine (Pinus taeda) plantations (YP2-7, 2-7 yrs old; YP2-8, 2-8 yrs old), a rotation-age loblolly pine plantation (MP, 15-28 yrs old), and a natural bottomland hardwood forest (BHF, > 100 yrs old) along the lower coastal plain of North Carolina. We quantified the differences in inter-annual and seasonal water balance and trends of evapotranspiration (ET) using eddy covariance over 37 site-years and assessed key climatic and biological drivers of ET. We found that the rotation-age plantation (MP) had higher annual ET (933 +/- 63 mm) than the younger plantations (776 +/- 74 mm for YP2-7 and 638 +/- 190 mm for YP2-8), and the BHF (743 +/- 172 mm), owing to differences in stand age, canopy cover, and micrometeorology. Chronosequence analysis of the pine sites showed that ET increased with stand age up to 10 years, then gradually stabilized for the remainder of the rotation of 28 - 30 years. YP2-8 was sensitive to water availability, decreasing ET by 30 - 43 % during the extreme 2007 - 2008 drought, but reductions in ET at MP were only 8 - 11 %. Comparing to BHF, ditching with management enhanced drainage at YP2-7 and YP2-8, while drainage was lower at the mature pine site. This study provides insight into land use-hydrology-climate interactions that have important implications for forested wetland management in a time of rapidly changing environmental conditions of the LCP of the southern US.

Published
2021

5. Shear velocity structure of the crust and upper mantle of Madagascar derived from surface wave tomography

Author

G. I. Aleqabi, Patrick J. Shore, Gérard Rambolamanana, Michael E. Wysession, Douglas A. Wiens, Tsiriandrimanana Rakotondraibe, Andrew A. Nyblade, E. J. Rindraharisaona, M. J. Pratt, Guilhem Barruol, Fenitra Andriampenomanana, Robert D. Tucker, Washington University in Saint Louis (WUSTL), Department of Geosciences, Pennsylvania State University (Penn State), Penn State System-Penn State System, Institut et Observatoire de Géophysique et Astronomie d'Antananarivo, Madagascar (IOGA), University of Maryland [College Park], University of Maryland System, Institut de Physique du Globe de Paris (IPGP), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire GéoSciences Réunion (LGSR), Université de La Réunion (UR)-Institut de Physique du Globe de Paris, GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), MACOMO project was provided by NSF award EAR-0838426DFG (Deutsche Forschungsgemeinschaft) grant SI1538/2-1, ANR-11-BS56-0013,RHUM-RUM,Imagerie mantellique du point chaud de La Réunion(2011), and Washington University in St Louis

Subjects
010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Volcanism, tomography, 010502 geochemistry & geophysics, ambient noise, 01 natural sciences, Geochemistry and Petrology, Asthenosphere, Madagascar, Earth and Planetary Sciences (miscellaneous), surface wave, 14. Life underwater, Shear velocity, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, ambient noise tomography, Crust, Sedimentary basin, Continental fragment, Geophysics, Space and Planetary Science, Magmatism, Intraplate earthquake, intraplate volcanism, Geology, Seismology
Abstract

International audience; The crust and upper mantle of the Madagascar continental fragment remained largely unexplored until a series of recent broadband seismic experiments. An island-wide deployment of broadband seismic instruments has allowed the first study of phase velocity variations, derived from surface waves, across the entire island. Late Cenozoic alkaline intraplate volcanism has occurred in three separate regions of Madagascar (north, central and southwest), with the north and central volcanism active until

Published
2017

6. Differential proteomics reveals novel insights into Nosema–honey bee interactions

Author

Julia Grassl, Yves Le Conte, Boris Baer, Ryan Dosselli, Robin F. A. Moritz, Per Kryger, Christoph Kurze, Institute for Biology-Molecular Ecology, Martin-Luther-Universität Halle Wittenberg (MLU), Centre for Integrative Bee Research (CIBER) and ARC Centre of Excellence in Plant Energy Biology, Bayliss Building (M316), The University of Western Australia (UWA), Center for Infectious Disease Dynamics, Pennsylvania State University (Penn State), Penn State System-Penn State System, Centre for Integrative Bee Research (CIBER) and ARC Centre of Excellence in Plant Energy Biology, Abeilles et Environnement (AE), Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU), Department of Agroecology/Section of Entomology and Plant Pathology, Aarhus University [Aarhus], Institute for Biology/Molecular Ecology, German Centre for Integrative Biodiversity Research, Department of Zoology and Entomology [Pretoria], University of Pretoria [South Africa], Deutsche Forschungsgemeinschaft DFG SPP 1399 MO373/26-2, Aarhus University, and Department of Zoology and Entomology

Subjects
Proteomics, 0106 biological sciences, 0301 basic medicine, Proteome, [SDV]Life Sciences [q-bio], approche protéomique, Bioinformatics, 01 natural sciences, Biochemistry, Mass Spectrometry, apis mellifera, Nosema, protéome, Genetics, tolerance, résistance aux parasites, Bees, host-parasite interaction, 3. Good health, coevolution, Host-Pathogen Interactions, Insect Proteins, Apis mellifera, Nosema ceranae, proteome, Biology, 010603 evolutionary biology, Fungal Proteins, 03 medical and health sciences, nosema ceranae, Animals, Host-parasite interaction, Molecular Biology, Gene, Host (biology), fungi, Honey bee, nosema apis, biology.organism_classification, interaction hôte parasite, Gastrointestinal Tract, 030104 developmental biology, coévolution, Insect Science, Adaptation, Tolerance
Abstract

Host-parasite interaction; Apis mellifera; Nosema ceranae; Tolerance; Proteome; Coevolution; Host manipulation is a common strategy by parasites to reduce host defense responses, enhance development, host exploitation, reproduction and, ultimately, transmission success. As these parasitic modifications can reduce host fitness, increased selection pressure may result in reciprocal adaptations of the host. Whereas the majority of studies on host manipulation have explored resistance against parasites (i.e. ability to prevent or limit an infection), data describing tolerance mechanisms (i.e. ability to limit harm of an infection) are scarce. By comparing differential protein abundance, we provide evidence of host-parasite interactions in the midgut proteomes of N. ceranae-infected and uninfected honey bees from both Nosema-tolerant and Nosema-sensitive lineages. We identified 16 proteins out of 661 protein spots that were differentially abundant between experimental groups. In general, infections of Nosema resulted in an up-regulation of the bee's energy metabolism. Additionally, we identified 8 proteins that were differentially abundant between tolerant and sensitive honey bees regardless of the Nosema infection. Those proteins were linked to metabolism, response to oxidative stress and apoptosis. In addition to bee proteins, we also identified 3 Nosema ceranae proteins. Interestingly, abundance of two of these Nosema proteins were significantly higher in infected Nosema-sensitive honeybees relative to the infected Nosema-tolerant lineage. This may provide a novel candidate for studying the molecular interplay between N. ceranae and its honey bee host in more detail.

Published
2016

7. Microcrystalline cellulose as reinforcing agent in silicone elastomers

Author

Sandra Binauld, Jean-Marc Frances, Gino Mangiante, Julien Bernard, S. Deng, Aurélia Charlot, Xin Zhou, Etienne Fleury, Shanghai Institute of Medical Mycology, Changzheng Hospital, Second Military Medical University, Ingénierie des Matériaux Polymères (IMP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS), Department of Crop and Soil Sciences, Pennsylvania State University (Penn State), Penn State System-Penn State System, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon

Subjects
Filler (packaging), Materials science, Polymers and Plastics, Surface Properties, Hydrosilylation, Microcrystalline cellulose, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, Silicone, Materials Chemistry, Silicone elastomer, Alkyne modification, Propargyl bromide, Cellulose, Composite material, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Biohybrids, Organic Chemistry, food and beverages, [CHIM.MATE]Chemical Sciences/Material chemistry, Polymer, 021001 nanoscience & nanotechnology, Grafting, 0104 chemical sciences, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Alkynes, Silicone Elastomers, 0210 nano-technology
Abstract

International audience; Cellulose is commonly used as filler for the reinforcement of polymer materials but data in the case of silicones remain rare. In this work we report the modification of microcrystalline cellulose (MCC) fibers from cotton linters by propargyl bromide, in aqueous medium without alteration of the crystalline domains. The analysis evidenced the efficient grafting of alkyne functions at the surface of the fibers, the DS being 0.5. The resulting MCC-Alkyne fibers were introduced within a bi-component reactive silicone formulation (up to 20 wt%), allowing the formation of network through hydrosilylation reaction in which MCC-Alkyne played the role of a reactive fillers. Comparison between the properties of composites prepared with unmodified MCC and MCC-Alkyne highlighted a densification of the network and an enhancement of mechanical and thermal properties when coupling reactions occurred. Mechanical properties of silicone elastomers were better if the load of MCC-Alkyne remains low.

Published
2016

8. In silico identification and structure function analysis of a putative coclaurine N-methyltransferase from Aristolochia fimbriata

Author

Roshan Ali, Ghosia Lutfulla, Claude W. dePamphilis, P. Kerr Wall, Simon G. Patching, Yuannian Jiao, Irshad Ahmad, Department of Biology [PennState], Pennsylvania State University (Penn State), Penn State System-Penn State System, The Astbury Centre for Structural Molecular Biology, University of Leeds, and School of Biomedical Sciences, University of Leeds

Subjects
Models, Molecular, 0301 basic medicine, Protein Conformation, Stereochemistry, [SDV]Life Sciences [q-bio], In silico, Aristolochia fimbriata, Biochemistry, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Biosynthesis, Structural Biology, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, [INFO]Computer Science [cs], Homology modeling, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, biology, Organic Chemistry, Computational Biology, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, Methyltransferases, Methylation, Aristolochia, biology.organism_classification, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, Computational Mathematics, 030104 developmental biology, Enzyme, chemistry, 030220 oncology & carcinogenesis, Aristolochiaceae, [INFO.INFO-BI]Computer Science [cs]/Bioinformatics [q-bio.QM], Coclaurine
Abstract

In this study we isolated and performed in silico analysis of a putative coclaurine N-methyltransferase (CNMT) from the basal angiosperm Aristolochia fimbriata. The Aristolochiaceae plant family produces alkaloids similar to the Papavaraceae family, and CNMTs are central enzymes in biosynthesis pathways producing compounds of ethnopharmacological interest. We used bioinformatics and computational tools to predict a three-dimensional homology model and to investigate the putative function of the protein and its mechanism for methylation. The putative CNMT is a unique (S)-adenosyl-L-methionine (SAM)-dependent N-methyltransferase, catalyzing transfer of a methyl group from SAM to the amino group of coclaurine. The model revealed a mixed α/β structure comprising seven twisted β-strands surrounded by twelve α-helices. Sequence comparisons and the model indicate an N-terminal catalytic Core domain and a C-terminal domain, of which the latter forms a pocket for coclaurine. An additional binding pocket for SAM is connected to the coclaurine binding pocket by a small opening. CNMT activity is proposed to follow an SN2-type mechanism as observed for a similarly conformed enzyme. Residues predicted for the methyl transfer reaction are Tyr79 and Glu96, which are conserved in the sequence from A. fimbriata and in homologous N-methyltransferases. The isolated CNMT is the first to be investigated from any basal angiosperm.

Published
2020

9. Enzymatic fingerprinting of arabinoxylan and β-glucan in triticale, barley and tritordeum grains

Author

Per Åman, Allah Rakha, Luc Saulnier, Rolf Andersson, University of Agriculture Faisalabad (UAF), Dept Food Sci, Pennsylvania State University (Penn State), Penn State System-Penn State System, Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Higher Education Commission (HEC), Pakistan, SLU Fund, VL-Foundation, and Barley Fun Food project

Subjects
0106 biological sciences, beta-Glucans, DIETARY FIBER, Polymers and Plastics, Oligosaccharides, Enzymatic fingerprinting, Biology, RHEOLOGICAL PROPERTIES, beta-Glucan, 01 natural sciences, chemistry.chemical_compound, 0404 agricultural biotechnology, Species Specificity, Barley, Tritordeum, [SDV.IDA]Life Sciences [q-bio]/Food engineering, Arabinoxylan, Materials Chemistry, STRUCTURAL FEATURES, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Cultivar, Trisaccharide, Genetic variability, Food science, WATER-SOLUBLE ARABINOXYLANS, Glucan, 2. Zero hunger, chemistry.chemical_classification, Organic Chemistry, food and beverages, Hordeum, CELL-WALL POLYSACCHARIDES, Triticale, 04 agricultural and veterinary sciences, OATS, 040401 food science, CEREAL-GRAINS, Agronomy, chemistry, PHYSICOCHEMICAL PROPERTIES, Xylanase, Xylans, Composition (visual arts), NONSTARCH POLYSACCHARIDES, Edible Grain, WHEAT-FLOUR, 010606 plant biology & botany
Abstract

International audience; Enzymatic fingerprinting of arabinoxylan (AX) and beta-glucan using endo-xylanase and lichenase, respectively, helps determine the structural heterogeneity between different cereals and within genotypes of the same cereal. This study characterised the structural features of AX and beta-glucan in whole grains of eight triticale cultivars grown at two locations, 20 barley cultivars/lines with wide variation in composition and morphology and five tritordeum breeding lines. Principal component analysis (PCA) resulted in clear clustering of these cereals. In general, barley and tritordeum had a higher relative proportion of highly branched arabinoxylan oligosaccharides (AXOS) than triticale. Subsequent analysis of triticale revealed two clusters based on growing region along principal component (PC) 1, while PC2 explained the genetic variability and was based on mono-substitution and di-substitution in AX fragments. PCA of p-glucan features separated the three cereals based on beta-glucan content. The molar ratio of trisaccharide to tetrasaccharide was 2.5-3.4 in triticale, 2.3-3.3 in barley and 2.8-3.4 in tritordeum. Barley showed a strong positive correlation (r = 0.86) between beta-glucan content and relative proportion of trisaccharide. The results show that structural features of AX and beta-glucan vary between and within triticale, barley and tritordeum grains which might be important determinants of end-use quality of grains. (c) 2012 Elsevier Ltd. All rights reserved.

Published
2012

10. Time evolution of the mineralogical composition of Mississippi Valley loess over the last 10kyr: Climate and geochemical modeling

Author

Susan L. Brantley, Yves Goddéris, D. Pollard, J. Z. Williams, Jacques Schott, Laboratoire des Mécanismes et Transfert en Géologie (LMTG), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Earth and environmental systems institute, Pennsylvania State University (Penn State), Penn State System-Penn State System, and Earth and Environmental Systems Institute

Subjects
010504 meteorology & atmospheric sciences, Dissolved silica, Dolomite, Pedosphere, Geochemistry, mississippi, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Climate change, modeling, Weathering, 010502 geochemistry & geophysics, loess, 01 natural sciences, modelling, 13. Climate action, Geochemistry and Petrology, Loess, weathering, climate, Geology, 0105 earth and related environmental sciences, Geochemical modeling, Hydrosphere
Abstract

Anthropogenic and natural climate change affect processes in the atmosphere, biosphere, hydrosphere, and pedosphere. The impact of climate on soil evolution has not been well-explored, largely due to slow rates and the complexity of coupled processes that must be observed and simulated. The rates of mineral weathering in loess deposited 23 kyr ago and experiencing soil formation for 13 kyr are explored here using the WITCH model for weathering and the GENESIS model for climate simulation. The WITCH model, which uses rigorous kinetic parameters and laws with provision for the effect on rates of deviation from equilibrium, can successfully simulate the depletion profiles in the soil for dolomite and albite if soil CO2 is assumed to rise over the last 10 kyr up to about 30–40× the present atmospheric pressure, and if the solubility product of the Ca-smectite is assumed equal to that of an Fe(III)-rich Ca-montmorillonite. Such simulations document that dissolution behavior for silicates and carbonates are strongly coupled through pH, and for Ca-smectite and feldspars through dissolved silica. Such coupling is not incorporated in simple geometric and analytical models describing mineral dissolution, and therefore probably contributes to the long-standing observation of discrepancies among laboratory and field mineral dissolution rates.

Published
2010

11. Hepatocyte transplantation (HTx) corrects selected neurometabolic abnormalities in murine intermediate maple syrup urine disease (iMSUD)

Author

Erland Arning, Kristen J. Skvorak, Erwin E.W. Jansen, Harbhajan S Paul, Qin Sun, K. Michael Gibson, C. Jakobs, Elizabeth J. Hager, Teodoro Bottiglieri, William J. Zinnanti, Gregg E. Homanics, Stephen C. Strom, Clinical chemistry, NCA - Childhood White Matter Diseases, Department of Pediatrics, University of Pittsburgh School of Medicine, Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), Children's Hospital of Pittsburgh of UPMC [Etats-Unis], Baylor University Medical Center, Baylor College of Medecine, Inc., Department of Pathology, Department of Anesthesiology, Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Baylor University-Baylor University, Department of Human Genetics, Graduate School of Public Health, Free University, Penn State College of Medicine, and Penn State System-Pennsylvania Commonwealth System of Higher Education (PCSHE)-Penn State System-Pennsylvania Commonwealth System of Higher Education (PCSHE)

Subjects
medicine.medical_specialty, Intracellular turnover, Biology, Models, Biological, Article, 03 medical and health sciences, chemistry.chemical_compound, Mice, GABA, 0302 clinical medicine, monoamines, large neutral amino acids, Maple Syrup Urine Disease, Leucine, Internal medicine, medicine, Animals, Humans, Neurotransmitter metabolism, Tyrosine, Molecular Biology, gamma-Aminobutyric Acid, 030304 developmental biology, Large neutral amino acid, 0303 health sciences, Neurotransmitter Agents, Monoamine, Maple syrup urine disease, Carnosine, Hepatocyte transplantation (HTx), Brain, Ornithine, medicine.disease, 3. Good health, Glutamine, Monoamine neurotransmitter, Endocrinology, chemistry, Liver, Hepatocytes, Molecular Medicine, Serotonin, 030217 neurology & neurosurgery
Abstract

International audience; Skvorak and coworkers [1] demonstrated the therapeutic efficacy of HTx in a murine model of iMSUD, confirming significant metabolic improvement and survival. To determine the effect of HTx on extrahepatic organs, we examined the metabolic effects of HTx in brain from iMSUD animals. Amino acid analysis revealed that HTx corrected increased ornithine, partially corrected depleted glutamine, and revealed a trend toward alloisoleucine correction. For amino acid and monoamine neurotransmitters, decreased GABA was partially corrected with HTx, while the L-histidine dipeptide of GABA, homocarnosine, was decreased in iMSUD mice and hypercorrected following HTx. Elevated branched chain amino acids (BCAA; leucine, isoleucine, valine) in MSUD can deplete brain tyrosine and tryptophan (the precursors of monoamine neurotransmitters dopamine (DA) and serotonin (5-hydroxytryptamine; 5-HT)) through competition via the large neutral amino acid transporter. HTx corrected decreased DA levels and the DA metabolite, 3-methoxytyramine, and partially corrected the DA intermediate 3,4-dihydroxyphenylacetate (DOPAC) and 5-HT levels, despite normal tyrosine and tryptophan levels in iMSUD mouse brain. We further observed enhanced intracellular turnover of both DA and 5-HT in iMSUD mouse brain, both of which partially corrected with HTx. Our results suggest new pathomechanisms of neurotransmitter metabolism in this disorder and support the therapeutic relevance of HTx in iMSUD mice, while providing proof-of-principle that HTx has corrective potential in extrahepatic organs.

Published
2009
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12. Trace element associations with Fe- and Mn-oxides in soil nodules: Comparison of selective dissolution with electron probe microanalysis

Author

Carmen Enid Martínez, Guilhem Bourrié, Alexander Neaman, Fabienne Trolard, Neaman, Alexander, Area de Medio Ambiente, Pontificia Universidad Católica de Valparaíso (PUCV), Centro Regional de Estudios en Alimentos Saludables (CREAS), Department of Crop and Soil Sciences, Pennsylvania State University (Penn State), Penn State System-Penn State System, Unité de recherche Géochimie des Sols et des Eaux (URGSE), and Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Nodule (geology), microsonde de castaing, [SDE.MCG]Environmental Sciences/Global Changes, Inorganic chemistry, méthode d'analyse, Electron microprobe, Fractionation, engineering.material, dissolution sélective, Citrate-bicarbonate-dithionite, chemistry.chemical_compound, étude des sols, Geochemistry and Petrology, Hydroxylamine-hydrochloride, Hydrogen-peroxide, Tropical-soil, EPMA, Iron-oxides, Manganese- oxides, Environmental Chemistry, Milieux et Changements globaux, Hydrogen peroxide, oxyde de manganèse, Dissolution, Electron probe microanalysis, élément trace, Chemistry, Trace element, oxyde de fer, Pollution, Agricultural sciences, Soil water, engineering, Sciences agricoles, Nuclear chemistry
Abstract

Selective dissolution methods have been largely used to get insight on trace element association with solid phases. Modern instrumental techniques offer many tools to test the validity of selective dissolution methods and should be systematically used to this end. The association of trace elements with Fe- and Mn-oxides in soil nodules has been studied here by electron probe microanalysis. The results were compared with findings from an earlier study on selective dissolution of the same nodules by hydroxylamine hydrochloride, acidified hydrogen peroxide, and Na-citrate-bicarbonate-dithionite. Electron probe microanalysis results were consistent with previous findings using selective dissolution and showed that P, As and Cr were mainly present in Fe-oxides, while Co was mainly associated with Mn-oxide phases. These results support the applicability of the studied selective dissolution methods for fractionation of trace elements in soils and sediments containing appreciable amounts of Fe and Mn-oxide phases.

Published
2008

13. A homogenization-based constitutive model for two-dimensional viscoplastic porous media

Author

Kostas Danas, Martín I. Idiart, P. Ponte Castañeda, Laboratoire de mécanique des solides (LMS), École polytechnique (X)-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Department of Engineering and Applied Mechanics, Pennsylvania State University (Penn State), and Penn State System-Penn State System

Subjects
Materials science, Strategy and Management, Constitutive equation, Porous media, 02 engineering and technology, [SPI.MECA.SOLID]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Solid mechanics [physics.class-ph], Plasticity, Homogenization (chemistry), Physics::Geophysics, law.invention, 0203 mechanical engineering, law, Transverse isotropy, Nonlinear composites, [PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph], Media Technology, Calculus, General Materials Science, Marketing, Homogenization, Viscoplasticity, Mechanics, 021001 nanoscience & nanotechnology, Nonlinear system, 020303 mechanical engineering & transports, Gurson criterion, Hydrostatic equilibrium, 0210 nano-technology, Porous medium
Abstract

An approximate model based on the so-called ‘second-order’ nonlinear homogenization method is proposed to estimate the effective behavior of viscoplastic porous materials exhibiting transversely isotropic symmetry. The model is constructed in such a way that it reproduces exactly the behavior of a ‘composite-cylinder assemblage’ in the limit of in-plane hydrostatic loading, and therefore coincides with the hydrostatic limit of Gurson's criterion for plastic porous materials. As a consequence, the new model improves on earlier ‘second-order’ homogenization estimates, which have been found to be overly stiff at sufficiently high triaxialities and nonlinearities. The proposed model is compared with exact results obtained for a special class of porous materials with sequentially laminated microstructures. The agreement is found to be excellent for the entire range of stress triaxialities, and all values of the porosity and nonlinearity considered. To cite this article: K. Danas et al., C. R. Mecanique 336 (2008).

Published
2008

14. Ginzburg–Landau minimizers with prescribed degrees. Capacity of the domain and emergence of vortices

Author

Leonid Berlyand, Petru Mironescu, Department of Mathematics, Pennsylvania State University (Penn State), Penn State System-Penn State System, Équations aux dérivées partielles, analyse (EDPA), Institut Camille Jordan [Villeurbanne] (ICJ), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Ginzburg–Landau vortices, Boundary (topology), Lambda, 01 natural sciences, Dirichlet distribution, Combinatorics, symbols.namesake, Simply connected space, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], 0101 mathematics, Mathematics, non compact, Conjecture, Degree (graph theory), 010102 general mathematics, Mathematical analysis, Harmonic map, vortices, Elliptic PDE's with lack of compactness, degree, 010101 applied mathematics, Domain (ring theory), symbols, Ginzburg-Landau, 58E50, 35J20, 49J10, Analysis
Abstract

International audience; Let $\Omega\subset {\mathbb R}^2$ be a simply connected domain, let $\omega$ be a simply connected subdomain of $\Omega$, and set $A=\Omega\setminus\overline\omega$. Let $J$ be the class of complex-valued maps on the annular domain $A$ with degree $1$ both on $\partial\Omega$ and on $\partial\omega$. We consider the variational problem of minimizing the Ginzburg- Landau energy $E_\lambda$ among all maps in $J$. Because only the degrees of the map are prescribed on the boundary, the set $J$ is not closed under weak $H^1$-convergence. We show that the attainability of the minimum of $E_\lambda$ over $J$ is determined by the value of cap$\,(A)$, where cap$\,(A)$ is the $H^1$-capacity of the domain $A$. In contrast, it is known that the existence of minimizers of $E_\lambda$ among the maps with a prescribed Dirichlet boundary data does not depend on this geometric characteristic. When cap$\,(A)\ge \pi$ (such an $A$ is denoted as either subcritical - if cap$\,(A)$>$\pi$ or critical - if cap$\,(A)= \pi$), we show that the global minimizers of $E_\lambda$ exist for each $\lambda>0$ and that they are vortexless when $\lambda$ is large. Assuming that $\lambda\to\infty$, we demonstrate that the minimizers of $E_\lambda$ converge in $H^1(A)$ (and even better) to an ${\mathbb S}^1$-valued harmonic map which we explicitly identify. When cap$\, (A)$$\lambda_0$, or (ii) the global minimizers exist for each $\lambda>0$. We conjecture that the second case never occurs. Further, for large $\lambda$, we establish that the minimizing sequences/minimizers in supercritical domains develop exactly two vortices - a vortex of degree $1$ near $\partial\Omega$ and a vortex of degree $-1$ near $\partial\omega$.

Published
2006
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15. Correlation between Vesicle Quantal Size and Fusion Pore Release in Chromaffin Cell Exocytosis

Author

Leslie A. Sombers, Andrew G. Ewing, Yann Bouret, Marie Erard, Stéphane Arbault, Imelda Bonifas, Christian Amatore, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), department of chemistry, Pennsylvania State University (Penn State), Penn State System-Penn State System, Laboratoire de Chimie Physique D'Orsay (LCPO), and Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chromaffin Cells, [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, Biophysics, Analytical chemistry, In Vitro Techniques, Biology, Membrane Fusion, Models, Biological, Biophysical Phenomena, Exocytosis, 03 medical and health sciences, Catecholamines, 0302 clinical medicine, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, medicine, Animals, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0303 health sciences, Fusion, Secretory Vesicles, Vesicle, Lipid bilayer fusion, Secretory Vesicle, Amperometry, Electrophysiology, Kinetics, medicine.anatomical_structure, Cell Biophysics, Chromaffin cell, Cattle, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], 030217 neurology & neurosurgery
Abstract

A significant number of exocytosis events recorded with amperometry demonstrate a prespike feature termed a "foot" and this foot has been correlated with messengers released via a transitory fusion pore before full exocytosis. We have compared amperometric spikes with a foot with spikes without a foot at chromaffin cells and found that the probability of detecting a distinct foot event is correlated to the amount of catecholamine released. The mean charge of the spikes with a foot was found to be twice that of the spikes without a foot, and the frequency of spikes displaying a foot was zero for small spikes increasing to approximately 50% for large spikes. It is hypothesized that in chromaffin cells, where the dense core is believed to nearly fill the vesicle, the expanding core is a controlling factor in opening the fusion pore, that prefusion of two smaller vesicles leads to excess membrane, and that this slows pore expansion leading to an increased observation of events with a foot. Clearly, the physicochemical properties of vesicles are key factors in the control of the dynamics of release through the fusion pore and the high and variable frequency of this release makes it highly significant.

Published
2005

16. Invariant Manifolds for a Class of Dispersive, Hamiltonian, Partial Differential Equations

Author

C. Eugene Wayne, Claude-Alain Pillet, Centre de Physique Théorique - UMR 6207 (CPT), Université de la Méditerranée - Aix-Marseille 2-Université de Provence - Aix-Marseille 1-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Department of Mathematics, Pennsylvania State University (Penn State), Penn State System-Penn State System, and Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Université de Provence - Aix-Marseille 1-Université de la Méditerranée - Aix-Marseille 2

Subjects
Partial differential equation, Applied Mathematics, [PHYS.MPHY]Physics [physics]/Mathematical Physics [math-ph], [MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS], 010102 general mathematics, Mathematical analysis, Invariant manifold, Invariant (physics), 01 natural sciences, Schrödinger equation, 010101 applied mathematics, symbols.namesake, [MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph], symbols, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], Periodic orbits, Scattering theory, 0101 mathematics, Hamiltonian (quantum mechanics), Mathematics::Symplectic Geometry, Analysis, Center manifold, Mathematics, Mathematical physics
Abstract

International audience; We construct an invariant manifold of periodic orbits for a class of non-linear Schrödinger equations. Using standard ideas of the theory of center manifolds, we rederive the results of Soffer and Weinstein (Comm. Math. Phys.133, 119–146 (1997);J. Differential Equations98, 376–390 (1992)) on the large time asymptotics of small solutions (scattering theory).

Published
1997

17. Accounting for misidentification and heterogeneity in occupancy studies using hidden Markov models

Author

Olivier Gimenez, Thierry Chambert, Julie Louvrier, Eric Marboutin, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Pennsylvania State University (Penn State), Penn State System, Oncfs, ONCFS, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Office National de la Chasse et de la Faune Sauvage (ONCFS), and Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
0106 biological sciences, Structure (mathematical logic), Flexibility (engineering), Detection heterogeneity, Interpretation (logic), Occupancy, Computer science, business.industry, 010604 marine biology & hydrobiology, Ecological Modeling, Occupancy models, Sampling (statistics), Accounting, Statistical model, Finite-mixture models, 010603 evolutionary biology, 01 natural sciences, False-positives, False positive paradox, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Species imperfect detection, business, Hidden Markov model, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; Occupancy models allow assessing species occurrence while accounting for imperfect detection. As with any statistical models, occupancy models rely on several assumptions amongst which (i) there should be no unmodelled heterogeneity in the detection probability and (ii) the species should not be detected when absent from a site, in other words there should be no false positives (e.g., due to misidentification). In the real world, thesetwo assumptions are often violated. To date, models accounting simultaneously for both detection heterogeneity and false positives are yet to be developed. Here, we first show how occupancy models with false positives can be formulated as hidden Markov models (HMM). Second, benefiting from the HMM framework flexibility, we extend models with false positives to account for heterogeneity with finite mixtures. First, using simulations, we demonstrate that, as the level of heterogeneity increases, occupancy models accounting for both heterogeneity and misidentification perform better in terms of bias and precision than models accounting for misidentification only. Next, we illustrate the implementation of our new model to a real case study with grey wolves (Canis lupus) in France. We demonstrate that heterogeneity in wolf detection (false negatives) is mainly due to a heterogeneous sampling effort across space. In addition to providing a novel modeling formulation, this work illustrates the flexibility of HMM framework to formulate complex ecological models and relax important assumptions that are not always likely to hold. In particular, we show how to decompose the model structure in several simple components, in a way that provides much clearer ecological interpretation.

Published
2018

18. Understanding the tensile strength of ceramics in the presence of small critical flaws

Author

Eric Martin, Oldřich Ševeček, Dominique Leguillon, Raul Bermejo, Laboratoire des Composites Thermostructuraux (LCTS), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Snecma-SAFRAN group-Centre National de la Recherche Scientifique (CNRS), Mécanique et Ingénierie des Solides Et des Structures (IJLRDA-MISES), Institut Jean Le Rond d'Alembert (DALEMBERT), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Brno University of Technology [Brno] (BUT), Montanuniversität Leoben (MUL), Pennsylvania State University (Penn State), Penn State System, and Centre National de la Recherche Scientifique (CNRS)-Snecma-SAFRAN group-Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Ceramics, Materials science, Finite Fracture Mechanics, 02 engineering and technology, Tensile strength, Finite fracture mechanics, [PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph], Stress (mechanics), 0203 mechanical engineering, Ultimate tensile strength, General Materials Science, Crack nucleation, Ceramic, [PHYS.COND.CM-SM]Physics [physics]/Condensed Matter [cond-mat]/Statistical Mechanics [cond-mat.stat-mech], Composite material, health care economics and organizations, Mechanical Engineering, Coupled criterion, 021001 nanoscience & nanotechnology, 020303 mechanical engineering & transports, Mechanics of Materials, visual_art, Fracture (geology), visual_art.visual_art_medium, Crystallite, 0210 nano-technology
Abstract

International audience; The effect of small critical flaws on the strength of polycrystalline ceramic materials is analyzed with the help of an initiation criterion combining both a stress and an energy conditions. If the size of the defect is smaller than the characteristic material length, numerical predictions reveal that the defect (either sharp or blunt) has no effect on the strength. This result is in a good agreement with experimental results obtained from the strength measurements of ceramic materials with controlled flaws. Combining two fracture tests after introducing flaws with controlled sizes enables to identify the fracture parameters of the ceramic material.

Published
2018

19. Dissipation of stop-and-go waves via control of autonomous vehicles: Field experiments

Author

Shumo Cui, Jonathan Sprinkle, Hannah Pohlmann, Miles Churchill, Benedetto Piccoli, Maria Laura Delle Monache, Rahul Bhadani, R’mani Haulcy, Daniel B. Work, Matt Bunting, Nathaniel Hamilton, Fangyu Wu, Benjamin Seibold, Raphael Stern, Department of Civil and Environmental Engineering [Urbana], University of Illinois at Urbana-Champaign [Urbana], University of Illinois System-University of Illinois System, Department of mathematics [Philadelphia], Temple University [Philadelphia], Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), Networked Controlled Systems (NECS), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Département Automatique (GIPSA-DA), Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Department of Electrical and Computer Engineering [Tucson] (ECE), University of Arizona, Lipscomb University [Nashville], Yale University [New Haven], Pennsylvania State University (Penn State), Penn State System, Rutgers University [Camden], Rutgers University System (Rutgers), and Pennsylvania Commonwealth System of Higher Education (PCSHE)

Subjects
Engineering, Traffic control, Flow (psychology), Autonomous vehicles, Transportation, Systems and Control (eess.SY), 010501 environmental sciences, Track (rail transport), 01 natural sciences, Control theory, 0502 economics and business, FOS: Electrical engineering, electronic engineering, information engineering, [INFO.INFO-SY]Computer Science [cs]/Systems and Control [cs.SY], Simulation, 0105 earth and related environmental sciences, Civil and Structural Engineering, Flow control (data), 050210 logistics & transportation, business.industry, 05 social sciences, Dissipation, Traffic flow, Traffic waves, Computer Science Applications, Automotive Engineering, Computer Science - Systems and Control, Actuator, business, Intelligent control, Traffic wave
Abstract

International audience; Traffic waves are phenomena that emerge when the vehicular density exceeds a critical threshold. Considering the presence of increasingly automated vehicles in the traffic stream, a number of research activities have focused on the influence of automated vehicles on the bulk traffic flow. In the present article, we demonstrate experimentally that intelligent control of an autonomous vehicle is able to dampen stop-and-go waves that can arise even in the absence of geometric or lane changing triggers. Precisely, our experiments on a circular track with more than 20 vehicles show that traffic waves emerge consistently, and that they can be dampened by controlling the velocity of a single vehicle in the flow. We compare metrics for velocity, braking events, and fuel economy across experiments. These experimental findings suggest a paradigm shift in traffic management: flow control will be possible via a few mobile actuators (less than 5%) long before a majority of vehicles have autonomous capabilities.

Published
2018

20. Characterization of the boron, lithium, and strontium isotopic variations of oil sands process-affected water in Alberta, Canada

Author

Romain Millot, Wolfram Kloppmann, Jason M. E. Ahad, Martine M. Savard, Paul Gammon, Avner Vengosh, Jennifer S. Harkness, Nathaniel R. Warner, Ania C. Ulrich, Nicholas School of the Environment, Duke University [Durham], Pennsylvania State University (Penn State), Penn State System, University of Alberta, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Geological Survey of Canada - Office (GSC), and Natural Resources Canada (NRCan)

Subjects
geography, geography.geographical_feature_category, Brackish water, Aquifer, 010501 environmental sciences, 010502 geochemistry & geophysics, Saline water, 01 natural sciences, Pollution, Tailings, 6. Clean water, Isotopes of strontium, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 13. Climate action, Geochemistry and Petrology, Environmental chemistry, Environmental Chemistry, Environmental science, Oil sands, Surface water, ComputingMilieux_MISCELLANEOUS, Groundwater, 0105 earth and related environmental sciences
Abstract

Oil sands operations in Alberta, Canada generate large volumes (>840 × 106 m3) of oil sands process-affected water (OSPW) that contains contaminants that are toxic to aquatic life. OSPW is stored in open tailings ponds and leakage from the ponds presents a potential long-term environmental risk. However, the presence of naturally occurring saline water in the oil sands region in Alberta presents a challenge for delineating the impact of OSPW in cases where OSPW is leaked to the environment. Here, we characterize the inorganic chemistry and isotopic variations of boron (δ11B), lithium (δ7Li), and strontium ( e S r S W ) of OSPW from tailings ponds in order to evaluate the source of salinity in OSPW and the potential utilization of these isotope ratios as forensic tracers of OSPW migration in the environment. In addition to generating new data, we compiled published data to build a comprehensive dataset of the geochemical composition of different water sources in the oil sands region of Alberta. OSPW is brackish (TDS ∼ 1800 mgL−1), with elevated chloride (392 ± 184 mg L−1), boron (2.2 ± 0.4 mg L−1), and lithium (0.12 ± 0.11 mg L−1) concentrations relative to the Athabasca River that is used for bitumen extraction. OSPW is characterized by narrow ranges of δ11B (23.7 ± 1.8‰), δ7Li (16.3 ± 1.7‰), and 87Sr/86Sr ratios ( e S r S W =-3.9 ± 19.2). The geochemical and isotope ratios in OSPW reflect mixing of residual, saline formation water from Lower Cretaceous units with fresh surface water that has been modified by interactions with the solid oil sands. The elevated boron and lithium concentrations and δ11B, δ7Li and e S r S W variations we observed are distinct from the compositions of a shallow freshwater aquifer in the area (8.1 ± 5.0‰, 11.3 ± 0.9‰ and 9.7 ± 5.6, respectively) and the local rivers (15.6 ± 4.7‰, 15.1 ± 1.4‰ and 30.3 ± 16.0). However, groundwater and saline springs in the region presents a wider range of geochemical and isotopic values that are not always distinguishable from OSPW. The integration of boron, lithium, and strontium isotopes provides a potential monitoring tool for tracing OSPW release to local freshwater sources.

Published
2018

21. Poincaré–Birkhoff–Witt isomorphisms and Kapranov dg-manifolds

Author

Mathieu Stiénon, Camille Laurent-Gengoux, Ping Xu, Institut Élie Cartan de Lorraine (IECL), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Pennsylvania State University (Penn State), Penn State System, Research partially supported by NSF grants DMS-2001599, DMS-1707545, DMS-1406668, DMS-1101827, and and NSA grant H98230-14-1-0153.

Subjects
Mathematics - Differential Geometry, Kapranov dg-manifolds, Pure mathematics, Algebraic structure, General Mathematics, Characterization (mathematics), 01 natural sciences, Mathematics - Algebraic Geometry, Poincaré–Birkhoff–Witt isomorphisms, Mathematics::K-Theory and Homology, Mathematics::Quantum Algebra, Mathematics - Quantum Algebra, 0103 physical sciences, Homotopy Lie algebras, Mathematics - Algebraic Topology, Lie theory, [MATH]Mathematics [math], 0101 mathematics, Mathematics::Symplectic Geometry, Mathematical Physics, ComputingMilieux_MISCELLANEOUS, Mathematics, Discrete mathematics, 010102 general mathematics, Lie algebroids, Exponential maps, Differential operator, Manifold, Bracket (mathematics), Symmetrization, 010307 mathematical physics, Isomorphism
Abstract

We prove that to every inclusion $A\hookrightarrow L$ of Lie algebroids over the same base manifold $M$ corresponds a Kapranov dg-manifold structure on $A[1]\oplus L/A$, which is canonical up to isomorphism. As a consequence, $\Gamma(\Lambda^\bullet A^\vee\otimes L/A)$ carries a canonical $L_\infty[1]$ algebra structure whose unary bracket is the Chevalley--Eilenberg differential corresponding to the Bott representation of $A$ on $L/A$ and whose binary bracket is a cocycle representative of the Atiyah class of the Lie pair $(L,A)$. To this end, we construct explicit isomorphisms of $C^\infty(M)$-coalgebras $\Gamma\big(S(L/A)\big)\xrightarrow{\sim}\frac{\mathcal{U}(L)}{\mathcal{U}(L)\Gamma(A)}$, which we elect to call Poincar\'e--Birkhoff--Witt maps. These maps admit a recursive characterization that allows for explicit computations. They generalize both the classical symmetrization map $S(\mathfrak{g})\to\mathcal{U}(\mathfrak{g})$ of Lie theory and (the inverse of) the complete symbol map for differential operators. Finally, we prove that the Kapranov dg-manifold $A[1]\oplus L/A$ is linearizable if and only if the Atiyah class of the Lie pair $(L,A)$ vanishes., Comment: 48 pages

Published
2021

22. Changes in the management of acne: 2009-2019

Author

Harald Gollnick, Valerie Sanders, Marie Jose Rueda, Diane Thiboutot, Brigitte Dréno, Malbec, Odile, Pennsylvania State University (Penn State), Penn State System, Nantes Université (Nantes Univ), Sanders Medical Writing [Pueblo West, CO, USA] (SMW), Eli Lilly and Company [Indianapolis], and Otto-von-Guericke-Universität Magdeburg = Otto-von-Guericke University [Magdeburg] (OVGU)

Subjects
Male, medicine.medical_specialty, antibiotic resistance, Time Factors, [SDV]Life Sciences [q-bio], Dermatology, Spironolactone, Severity of Illness Index, Drug Administration Schedule, Antimicrobial Stewardship, Sex Hormone-Binding Globulin, Acne Vulgaris, Drug Resistance, Bacterial, medicine, Humans, guidelines, Isotretinoin, acne, ComputingMilieux_MISCELLANEOUS, Acne, Benzoyl Peroxide, business.industry, medicine.disease, Anti-Bacterial Agents, [SDV] Life Sciences [q-bio], Practice Guidelines as Topic, Female, business, Contraceptives, Oral
Abstract

International audience; No abstract available

Published
2020

23. Modeling the burden of poultry disease on the rural poor in Madagascar

Author

Ranto Ramananjato, Cara E. Brook, Thomas R. Gillespie, Andres Garchitorena, Matthew H. Bonds, Patricia C. Wright, Calistus N. Ngonghala, Milijaona Randrianarivelojosia, Ann C. Miller, Cassidy Rist, Emory University [Atlanta, GA], Harvard Medical School [Boston] (HMS), Maladies infectieuses et vecteurs : écologie, génétique, évolution et contrôle (MIVEGEC), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), École des Hautes Études en Santé Publique [EHESP] (EHESP), Department of Ecology and Evolutionary Biology [Princeton], Princeton University, Institut National de la Statistique (INS), Institut national de la statistique, Pennsylvania State University (Penn State), Penn State System, Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP), Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Department of Anthropology [Stony Brook University], State University of New York (SUNY)-State University of New York (SUNY), Department of Geography, University of California [Los Angeles] (UCLA), University of California-University of California, Stanford University, and University of California (UC)-University of California (UC)

Subjects
Livestock, Economics, Developing country, Human capital, Poultry, Agricultural economics, 03 medical and health sciences, Infectious disease modeling, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, Environmental health, 0502 economics and business, medicine, 050207 economics, Poverty, Disease burden, 030304 developmental biology, 2. Zero hunger, lcsh:R5-920, 0303 health sciences, Food security, business.industry, 05 social sciences, 1. No poverty, Public Health, Environmental and Occupational Health, medicine.disease, Infectious Diseases, Infectious disease (medical specialty), Poultry disease, lcsh:Medicine (General), business, Research Paper
Abstract

Livestock represent a fundamental economic and nutritional resource for many households in the developing world; however, a high burden of infectious disease limits their production potential. Here we present an ecological framework for estimating the burden of poultry disease based on coupled models of infectious disease and economics. The framework is novel, as it values humans and livestock as co-contributors to household wellbeing, incorporating feedbacks between poultry production and human capital in disease burden estimates. We parameterize this coupled ecological–economic model with household-level data to provide an estimate of the overall burden of poultry disease for the Ifanadiana District in Madagascar, where over 72% of households rely on poultry for economic and food security. Our models indicate that households may lose 10–25% of their monthly income under current disease conditions. Results suggest that advancements in poultry health may serve to support income generation through improvements in both human and animal health., Highlights • We describe a new framework that couples models of infectious disease ecology and economics. • Using this framework, we estimate the burden of poultry disease on rural households in Madagascar. • We find that monthly household income is reduced by 10–25% in the majority of model simulations. • Feedbacks between human and poultry productivity amplify the economic impact of poultry disease.

Published
2015

24. Hydrodynamic modelling of marine renewable energy devices: A state of the art review

Author

F. Salvatore, Aurélien Babarit, Yan Ping He, Motohiko Murai, M Kraskowski, A Fontaine, Alexander Day, Irene Penesis, Hyunkyoung Shin, University of Strathclyde [Glasgow], Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique (LHEEA), École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), Pennsylvania State University (Penn State), Penn State System, Shanghai Jiao Tong University [Shanghai], Centrum Techniki Okrętowej, Yokohama National University, Australian Maritime College (AMC), University of Tasmania [Hobart, Australia] (UTAS), Istituto Nazionale per Studi ed Esperienze di Architettura Navale, and University of Ulsan

Subjects
Engineering, Environmental Engineering, VM, 020209 energy, Ocean Engineering, Context (language use), 02 engineering and technology, 7. Clean energy, 01 natural sciences, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], 010305 fluids & plasmas, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Performance prediction, Hydrodynamic modelling, Power take-off, Marine renewable energy, Towing, business.industry, [SPI.NRJ]Engineering Sciences [physics]/Electric power, Wind engineering, Renewable energy, Offshore wind power, 13. Climate action, Marine renewableenergy, business, Tidal power, Marine engineering
Abstract

International audience; This paper reviews key issues in the physical and numerical modelling of marine renewable energy systems, including wave energy devices, current turbines, and offshore wind turbines. The paper starts with an overview of the types of devices considered, and introduces some key studies in marine renewable energy modelling research. The development of new International Towing Tank Conference (ITTC) guidelines for model testing these devices is placed in the context of guidelines developed or under development by other international bodies as well as via research projects. Some particular challenges are introduced in the experimental and numerical modelling and testing of these devices, including the simulation of Power-Take-Off systems (PTOs) for physical models of all devices, approaches for numerical modelling of devices, and the correct modelling of wind load on offshore wind turbines. Finally, issues related to the uncertainty in performance prediction from model test results are discussed.The paper is based on the report of the International Towing Tank Conference specialist committee on Hydrodynamic Modelling of Marine Renewable Energy Devices to the 27th ITTC held in Copenhagen, Denmark in 2014 (ITTC Specialist Committee on Hydrodynamic Modelling of Marine Renewable Energy Devices, 2014a. Final Report and Recommendations to the 27th ITTC Proc. 27th International Towing Tank Conference, Copehagen, Denmark, vol. 2, pp. 680–725).

Published
2015

25. Oxygen-related chemoreceptor drive to breathe during H2S infusion

Author

Takashi Sonobe, Bruno Chenuel, Philippe Haouzi, Penn State Health Milton S. Hershey Medical Center, Pennsylvania Commonwealth System of Higher Education (PCSHE)-Penn State System, Développement, Adaptation et Handicap. Régulations cardio-respiratoires et de la motricité (DevAH), and Université de Lorraine (UL)

Subjects
Pulmonary and Respiratory Medicine, Hyperoxia, Chemoreceptor, Physiology, Chemistry, General Neuroscience, Stimulation, Hyperpnea, equipment and supplies, medicine.disease, 3. Good health, Tonic (physiology), Anesthesia, Respiration, medicine, Arterial blood, medicine.symptom, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology, Respiratory minute volume
Abstract

International audience; This study addresses the following question: Could the acute depression in breathing produced by hyperoxia, a reflection of the tonic drive to breathe from the arterial chemoreceptors, be accounted for by the presence a background level of local endogenous H2S? To address this question, we produced a stable but moderate increase in breathing (24 ± 11%) via continuous infusion of low levels of H2S, in 10 spontaneously breathing urethane-sedated rats. We found that acute exposure to 100% O2 (20 tests) decreased minute ventilation (VI) from 301 ± 51 to 210 ± 43 ml/min within 15 seconds in control conditions, but no additional significant drop in VI was observed during H2S induced hyperpnea. In addition, no decrease in the estimated concentrations of gaseous H2S in the arterial blood was observed during the hyperoxic tests. It is concluded that the ventilatory depression induced by high O2 appears to be limited to the tonic background peripheral chemosensory drive to breathe, but has little or no impact on the CB stimulation produced by low levels of H2S.

Published
2014

26. Sintering behavior and non-linear properties of ZnO varistors processed in microwave electric and magnetic fields at 2.45GHz

Author

Etienne Savary, Dinesh K. Agrawal, Sylvain Marinel, Romain Heuguet, Alexandre Badev, Laboratoire de cristallographie et sciences des matériaux (CRISMAT), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Matériaux Céramiques et Procédés Associés - EA 2443 (LMCPA), Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Pennsylvania State University (Penn State), Penn State System, Axe 1 : procédés céramiques, Science des Procédés Céramiques et de Traitements de Surface (SPCTS), Université de Limoges (UNILIM)-Ecole Nationale Supérieure de Céramique Industrielle (ENSCI)-Institut des Procédés Appliqués aux Matériaux (IPAM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Ecole Nationale Supérieure de Céramique Industrielle (ENSCI)-Institut des Procédés Appliqués aux Matériaux (IPAM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Institut de Chimie du CNRS (INC)

Subjects
Materials science, Polymers and Plastics, Analytical chemistry, Sintering, 02 engineering and technology, 01 natural sciences, 7. Clean energy, Powder metallurgy, Electric field, 0103 physical sciences, Varistor, [CHIM]Chemical Sciences, Microstructure, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, Surface diffusion, Metals and Alloys, [CHIM.MATE]Chemical Sciences/Material chemistry, Breakdown voltage, 021001 nanoscience & nanotechnology, Grain size, Electronic, Optical and Magnetic Materials, Grain growth, Ceramics and Composites, 0210 nano-technology, Microwave
Abstract

International audience; A study of the densification behavior and grain growth mechanisms of ZnO-based varistors composed of 98 mol.% ZnO–2 mol.% (Bi2O3, Sb2O3, Co3O4, MnO2) has been carried out. The pressed samples were sintered in microwave electric (E) and magnetic (H) fields using a single-mode cavity of 2.45 GHz. The effect of the sintering temperature (900–1200 °C), holding time (5–120 min) and sintering mode (E, H) on the microstructure and electrical properties of the sintered varistor samples were investigated. The grain growth kinetics was studied using the simplified phenomenological equation Gn = kte(−Q/RT). The grain growth exponent (n) and apparent activation energy (Q) values were estimated for both electric and magnetic heating modes and were found to be n = 3.06–3.27, Q = 206–214 kJ mol−1, respectively. The lower value of n estimated in the E field was attributed to a volume diffusion mechanism, whereas the higher n value in the H field sintering was correlated mainly to a combined effect of volume and surface diffusion processes. Samples sintered in the H and E fields showed high final densities. Moreover, the ones sintered in the H field presented slightly higher density values and bigger grains for all sintering temperatures than E field heated ones. The optimal sintering conditions were achieved at 1100 °C for a 5 min soaking time for both H and E field processed samples, where respectively densities of 99.2 ± 0.5% theoretical density (TD) and 98.3 ± 0.5% TD along with grain size values of G = 7.2 ± 0.36 μm and G = 6.6 ± 0.33 μm were obtained. Regarding the electrical properties, breakdown voltage values as high as 500–570 V mm−1 were obtained, together with high non-linear coefficients α = 29–39 and low leakage currents (Jl ≈ 5 × 10−3 mA cm−2), respectively, for E and H field sintered varistor samples. Moreover, samples sintered in an H field systematically exhibited higher breakdown voltage values compared to the ones sintered in the E field. This was attributed to an improved coupling between the H field and the present dopants within the ZnO matrix, this latter being mostly semiconductive, thus leading to an enhanced reactivity and improved properties of the electrostatic barrier.

Published
2013

27. Fretting corrosion with proteins: The role of organic coating on the synergistic mechanisms

Author

Jean Geringer, Digby D. Macdonald, Matthew L. Taylor, Julie Pellier, Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, INSERM, U 1059 Sainbiose, Centre CIS, F - 42023 Saint-Etienne France, Pennsylvania State University (Penn State), Penn State System, Centre Ingénierie et Santé (CIS-ENSMSE), École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire Georges Friedel (LGF-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Surfaces et Tissus Biologiques (STBio-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-CIS, Institut Fédératif de Recherche en Sciences et Ingénierie de la Santé (IFRESIS-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-IFR143, UMR 5146 - Laboratoire Claude Goux (LCG-ENSMSE), Département Biomécanique et Biomatériaux (DB2M-ENSMSE), Department of Materials Science and Engineering (DMSE), University of Pennsylvania [Philadelphia], Gregory Abadias, Samir Aouadi, Ivan Petrov, Claus Rebholz, Michael Stüber and Stan Veprek, University Park, Center for Electrochemical Science and Technology, and Materials Science and Engineering

Subjects
Materials science, Fretting-corrosion, Ionic bonding, Fretting, 02 engineering and technology, engineering.material, Corrosion, Metal, [SPI]Engineering Sciences [physics], 0203 mechanical engineering, Coating, 316L, Materials Chemistry, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, [PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph], [SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/Biomaterials, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, Albumin, Metallurgy, Synergism, Metals and Alloys, [SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph], Surfaces and Interfaces, Polymer, 021001 nanoscience & nanotechnology, PMMA, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 020303 mechanical engineering & transports, chemistry, Chemical engineering, Ionic strength, visual_art, visual_art.visual_art_medium, engineering, Degradation (geology), 0210 nano-technology
Abstract

International audience; Fretting corrosion is one of the most deleterious mechanisms for the degradation of metallic biomaterials, especially in the orthopedic field. This work is dedicated to studying the synergistic effect of proteins and ionic concentration on the wear of 316L stainless steel against a polymer sample under fretting-corrosion conditions. A specialized device produces repeatable fretting corrosion conditions. In order to compare with previous investigations, the relative displacement was chosen to be ± 40 μm in a sinusoidal pattern. The duration of each test was 14,400 s. 4 solutions of NaCl were selected in order to study the effect of the ionic strength: 10− 3 mol L− 1, 10− 2 mol L− 1, 10− 1 mol L− 1 and 1 mol L− 1. In addition to NaCl, the following concentrations of proteins (in this case, pure albumin) were considered: 0, 1 and 20 g L− 1. Experiments were carried out at a temperature of 22 ± 1 °C. Measurements were obtained at open circuit potential, (OCP). During other experiments, the applied potential was equal to − 400 mV/SCE and the current density was measured. An integrated analytical approach was used in order to elucidate the synergy between mechanics and corrosion. The most interesting finding is that albumin changes the mode of synergy. At 0 g L− 1 of albumin, the main synergistic term is the influence of mechanics on corrosion. On the contrary, at 20 g L− 1, the main synergistic term is the influence of corrosion on mechanics

Published
2013

28. Broadband dielectric characterization of TiO2 ceramics sintered through microwave and conventional processes

Author

Dinesh K. Agrawal, Sylvain Marinel, Michael T. Lanagan, Doo Hyun Choi, Romain Heuguet, Laboratoire de cristallographie et sciences des matériaux (CRISMAT), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), Pennsylvania State University (Penn State), Penn State System, Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Microwave processing, Materials science, Annealing (metallurgy), Sintering, 02 engineering and technology, Dielectric, 7. Clean energy, 01 natural sciences, law.invention, law, 0103 physical sciences, Materials Chemistry, TiO2, [CHIM]Chemical Sciences, Ceramic, Composite material, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, Process Chemistry and Technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Grain size, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Dielectric properties, visual_art, Ceramics and Composites, visual_art.visual_art_medium, Dielectric loss, 0210 nano-technology, Microwave, Susceptor
Abstract

International audience; In this work the microwave sintering (MW) of pure submicron rutile TiO2 powder has been conducted in complete electric field using a single mode cavity of 2.45 GHz and without any susceptor. The sintering conditions were varied and similar sintering cycles were also done using a conventional furnace (CV), in carefully measuring the temperature in both processes. The dielectric properties, from kHz to GHz were determined and a comparison analysis was made between microwaved and conventional sintered specimens. It is shown that microwave sintering allows to obtain dense material (>95%) in a very short time (10–15 min) at a sintering temperature ranging from 1000 °C to 1300 °C. Some samples are fully dense (>99% theoretical density) after being microwave heated for ∼10 min at ∼1300 °C. Using the microwave heating, the processing temperature to get high dense material (i.e. >94%) is lowered by ∼150–175 °C compared to conventionally sintered samples. It is also shown that an annealing in air at ∼800 °C for ∼4 h, leads to very low loss TiO2 ceramic in the entire frequency range investigated. Owing to the lowest sintering temperature provided by microwaves, the low frequency dielectric losses are smaller for MW samples than for CV sintered samples. Among the highest reported microwave Q factors (∼7350) have been measured on pure TiO2 samples exhibiting the largest grain size (∼1.5 μm) and density (>96%).

Published
2013

29. Community-Driven Data Analysis Training for Biology

Author

Dannon Baker, Aisanjiang Wubuli, Anthony Bretaudeau, Saskia Hiltemann, John Chilton, Bérénice Batut, Vivek Bhardwaj, Thomas Manke, Loraine Brillet-Guéguen, Mallory A. Freeberg, Olivia Doppelt-Azeroual, Fabien Mareuil, Gildas Le Corguillé, Nicola Soranzo, Fidel Ramírez, Joachim Wolff, Clemens Blank, Rolf Backofen, Anton Nekrutenko, Pavankumar Videm, Youri Hoogstrate, Dave Clements, Dilmurat Yusuf, Delphine Larivière, Markus Wolfien, Anika Erxleben, Simon Gladman, Devon Ryan, James Taylor, Florian Christoph Sigloch, Björn Grüning, Hans-Rudolf Hotz, Torsten Houwaart, Pratik D. Jagtap, Martin Čech, Andrea Bagnacani, Bioinformatics Group [Freiburg], Department of Computer Science [Freiburg], Albert-Ludwigs-Universität Freiburg-Albert-Ludwigs-Universität Freiburg, Erasmus University Medical Center [Rotterdam] (Erasmus MC), Department of Systems Biology and Bioinformatics, University of Rostock, Johns Hopkins University (JHU), Department of Biology [Fribourg], University of Freiburg [Freiburg], Plateforme bioinformatique GenOuest [Rennes], Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Plateforme Génomique Santé Biogenouest®-Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-GESTION DES DONNÉES ET DE LA CONNAISSANCE (IRISA-D7), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National de Recherche en Informatique et en Automatique (Inria)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-CentraleSupélec-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Bretagne Sud (UBS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Institut de Génétique, Environnement et Protection des Plantes (IGEPP), Institut National de la Recherche Agronomique (INRA)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), ABiMS - Informatique et bioinformatique = Analysis and Bioinformatics for Marine Science (FR2424), Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Pennsylvania State University (Penn State), Penn State System, Hub Bioinformatique et Biostatistique - Bioinformatics and Biostatistics HUB, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), European Bioinformatics Institute [Hinxton] (EMBL-EBI), EMBL Heidelberg, Melbourne Bioinformatics [Australia], University of Melbourne, Friedrich Miescher Institute for Biomedical Research (FMI), Novartis Research Foundation, University of Minnesota Medical School, University of Minnesota System, Max Planck Institute of Immunobiology and Epigenetics (MPI-IE), Max-Planck-Gesellschaft, Earlham Institute [Norwich], Leibniz Institute for Farm Animal Biology (FBN), This project was supported by Collaborative Research Centre 992 Medical Epigenetics (DFG grant SFB 992/1 2012), German Federal Ministry of Education and Research (BMBF grant 031 A538A RBC [de.NBI]), NIH grants U41 HG006620 and R01 AI134384-01, as well as NSF grant 1661497., The authors are grateful to the Freiburg Galaxy and Core Galaxy teams as, without these resources, this work would not be possible. Adoption of Galaxy Tours has been accelerated with the introduction of Galaxy Tour Builder (https://zenodo.org/record/830481) by William Durand (https://tailordev.fr)., Galaxy Training Network, Pathology, Urology, Université de Rennes (UR)-Plateforme Génomique Santé Biogenouest®-Inria Rennes – Bretagne Atlantique, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Université de Rennes (UR)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-INSTITUT AGRO Agrocampus Ouest, ABiMS - Informatique et bioinformatique = Analysis and Bioinformatics for Marine Science (ABIMS), Fédération de recherche de Roscoff (FR2424), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0301 basic medicine, Histology, data analysis, Space (commercial competition), Training (civil), Article, Pathology and Forensic Medicine, Education, Distance, 03 medical and health sciences, proteomics, 0302 clinical medicine, Software, ComputingMilieux_COMPUTERSANDEDUCATION, genomics, Feature (machine learning), Humans, Curriculum, Web browser, training, business.industry, 4. Education, Computational Biology, Cell Biology, Data science, Research Personnel, 030104 developmental biology, Key (cryptography), Data analysis, next-generation sequencing, [INFO.INFO-BI]Computer Science [cs]/Bioinformatics [q-bio.QM], business, 030217 neurology & neurosurgery
Abstract

La version finale de l'article a été déposée sur PMC. The final version of this article has been deposed on PMC; The primary problem with the explosion of biomedical datasets is not the data, not computational resources, and not the required storage space, but the general lack of trained and skilled researchers to manipulate and analyze these data. Eliminating this problem requires development of comprehensive educational resources. Here we present a community-driven framework that enables modern, interactive teaching of data analytics in life sciences and facilitates the development of training materials. The key feature of our system is that it is not a static but a continuously improved collection of tutorials. By coupling tutorials with a web-based analysis framework, biomedical researchers can learn by performing computation themselves through a web browser without the need to install software or search for example datasets. Our ultimate goal is to expand the breadth of training materials to include fundamental statistical and data science topics and to precipitate a complete re-engineering of undergraduate and graduate curricula in life sciences. This project is accessible at https://training.galaxyproject.org.

Published
2018

30. Evaluation of ocean model ventilation with CFC-11: comparison of 13 global ocean models

Author

Jean-Claude Dutay, John Marshall, Gurvan Madec, Akio Ishida, J.-M. Campin, Anne Mouchet, Ken Caldeira, Richard D. Slater, Yongqi Gao, Andrew Yool, Yasuhiro Yamanaka, John L. Bullister, Helge Drange, Gian-Kasper Plattner, Michael J. Follows, Jorge L. Sarmiento, Richard J. Matear, Scott C. Doney, Marie-France Weirig, Ernst Maier-Reimer, Raymond G. Najjar, Keith Lindsay, Patrick Monfray, Fortunat Joos, Matthew W. Hecht, Nicolas Gruber, I. Totterdell, Reiner Schlitzer, James C. Orr, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Modélisation du climat (CLIM), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), NOAA Pacific Marine Environmental Laboratory [Seattle] (PMEL), National Oceanic and Atmospheric Administration (NOAA), National Center for Atmospheric Research [Boulder] (NCAR), Pennsylvania State University (Penn State), Penn State System, Lawrence Livermore National Laboratory (LLNL), Institut d'Astronomie et de Géophysique Georges Lemaître (UCL-ASTR), Université Catholique de Louvain = Catholic University of Louvain (UCL), Nansen Environmental and Remote Sensing Center [Bergen] (NERSC), Massachusetts Institute of Technology (MIT), Atmospheric and Oceanic Sciences Program [Princeton] (AOS Program), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA)-National Oceanic and Atmospheric Administration (NOAA)-Princeton University, Research Institute for Global Change (RIGC), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Oeschger Centre for Climate Change Research (OCCR), University of Bern, Climate and Global Dynamics Division [Boulder] (CGD), Laboratoire d'océanographie dynamique et de climatologie (LODYC), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Meteorology (MPI-M), Max-Planck-Gesellschaft, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Astrophysics and Geophysics Institute [Liège], Université de Liège, Institute of Applied Physics [Bern] (IAP), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), National Oceanography Centre [Southampton] (NOC), University of Southampton, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Universität Bern [Bern]-Universität Bern [Bern]

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Ocean ventilation, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Physical oceanography, Oceanography, 01 natural sciences, Bottom water, Models, Ocean gyre, Computer Science (miscellaneous), 14. Life underwater, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, 010505 oceanography, North Atlantic Deep Water, Geotechnical Engineering and Engineering Geology, Ocean dynamics, Antarctic Bottom Water, CFC, 13. Climate action, Climatology, Thermohaline circulation, Ocean heat content, Transient tracers, Geology
Abstract

International audience; We compared the 13 models participating in the Ocean Carbon Model Intercomparison Project (OCMIP) with regards to their skill in matching observed distributions of CFC-11. This analysis characterizes the abilities of these models to ventilate the ocean on timescales relevant for anthropogenic CO2 uptake. We found a large range in the modeled global inventory (±30%), mainly due to differences in ventilation from the high latitudes. In the Southern Ocean, models differ particularly in the longitudinal distribution of the CFC uptake in the intermediate water, whereas the latitudinal distribution is mainly controlled by the subgrid-scale parameterization. Models with isopycnal diffusion and eddy-induced velocity parameterization produce more realistic intermediate water ventilation. Deep and bottom water ventilation also varies substantially between the models. Models coupled to a sea-ice model systematically provide more realistic AABW formation source region; however these same models also largely overestimate AABW ventilation if no specific parameterization of brine rejection during sea-ice formation is included. In the North Pacific Ocean, all models exhibit a systematic large underestimation of the CFC uptake in the thermocline of the subtropical gyre, while no systematic difference toward the observations is found in the subpolar gyre. In the North Atlantic Ocean, the CFC uptake is globally underestimated in subsurface. In the deep ocean, all but the adjoint model, failed to produce the two recently ventilated branches observed in the North Atlantic Deep Water (NADW). Furthermore, simulated transport in the Deep Western Boundary Current (DWBC) is too sluggish in all but the isopycnal model, where it is too rapid.

Published
2002

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