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1. Holocene palaeohydrological changes in the northern Mediterranean borderlands as reflected by the lake-level record of Lake Ledro, northeastern Italy

Author

Romana Scandolari, Michel Magny, Michele Bassetti, Sébastien Joannin, P. Bellintani, Marc Desmet, Boris Vannière, Jean Nicolas Haas, Didier Galop, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux ( MSHE ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] ( LGL-TPE ), École normale supérieure - Lyon ( ENS Lyon ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Géographie de l'environnement ( GEODE ), Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse - Jean Jaurès ( UT2J ), University of Innsbruck, Department of Botany, Universita 'La Sapienza' Roma ( Istituto CNR ), Università degli Studi di Roma 'La Sapienza' [Rome], Soprintendenza per i Beni Archeologici di trento, Museo delle Palafitte del Lago di Ledro, Musée de Ledro, École Nationale des Travaux Publics de l'État ( ENTPE ), École Nationale des Travaux Publics de l'État ( ENTPE ) -Ministère de l'Ecologie, du Développement Durable, des Transports et du Logement, Institut des Sciences de la Terre d'Orléans ( ISTO ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université d'Orléans ( UO ) -Université de Tours-Centre National de la Recherche Scientifique ( CNRS ), ANR-05-BLAN-0140,JCLAMA,Méthodes mixtes, visualisation et optimisation ( 2005 ), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux (MSHE), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Géographie de l'environnement (GEODE), Université Toulouse - Jean Jaurès (UT2J)-Centre National de la Recherche Scientifique (CNRS), Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Transferts continentaux : forçages anthropiques, climatiques et géodynamiques, Institut des Sciences de la Terre d'Orléans (ISTO), Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), ANR-05-BLAN-0140,JCLAMA,Méthodes mixtes, visualisation et optimisation(2005), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Maison des Sciences de l'Homme et de l'Environnement Claude Nicolas Ledoux (UAR 3124) (MSHE), Université de Tours (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chrono-environnement (UMR 6249) (LCE), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Universität Innsbruck [Innsbruck], and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)

Subjects
Mediterranean climate, 010506 paleontology, 010504 meteorology & atmospheric sciences, Lacustrine sediments, Mediterranean, 01 natural sciences, [ SHS.ENVIR ] Humanities and Social Sciences/Environmental studies, law.invention, Arts and Humanities (miscellaneous), law, Littoral zone, Deglaciation, Radiocarbon dating, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes, Mediterranean Lake-level fluctuations Lacustrine sediments Palaeohydrology Holocene, Preboreal, Boreal, 13. Climate action, Climatology, [SHS.ENVIR]Humanities and Social Sciences/Environmental studies, General Earth and Planetary Sciences, Palaeohydrology, Physical geography, Geology, Chronology, Lake-level fluctuations
Abstract

A lake-level record of Lake Ledro (northern Italy) spans the entire Holocene with a chronology derived from 51 radiocarbon dates. It is based on a specific sedimentological approach that combines data from five sediment profiles sampled in distinct locations in the littoral zone. On a millennial scale, the lake-level record shows two successive periods from 11,700 to 4500 cal yr BP and from 4500 cal yr BP to the present, characterized by lower and higher average lake levels, respectively. In addition to key seasonal and inter-hemispherical changes in insolation, the major hydrological change around 4500 cal yr BP may be related to a non-linear response of the climate system to orbitally-driven gradual decrease in insolation. The Ledro record questions the notion of an accentuated summer rain regime in the northern Mediterranean borderlands during the boreal insolation maximum. Moreover, the Ledro record highlights that the Holocene was punctuated by successive centennial-scale highstands. Correlations with the Preboreal oscillation and the 8.2 ka event, and comparison with the atmospheric 14C residual record, suggest that short-lived lake-level fluctuations developed at Ledro in response to (1) final steps of the deglaciation in the North Atlantic area and (2) variations in solar activity.

Published
2012
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2. Determinants of downloads and citations for articles published in Intensive Care Medicine

Author

Timsit, J., Citerio, G., Lavilloniere, M., Perner, A., Ruckly, S., Bakker, J., Bassetti, M., Benoit, D., Curtis, J.R., Doig, G.S., Herridge, M., Jaber, Samir, Papazian, L., Peters, J., Peters, M.J., Singer, P., Smith, M., Soares, M., Torres, A., Vieillard-Baron, A., Azoulay, E., Timsit, J, Citerio, G, Lavilloniere, M, Perner, A, Ruckly, S, Bakker, J, Bassetti, M, Benoit, D, Curtis, J, Doig, G, Herridge, M, Jaber, S, Papazian, L, Peters, M, Singer, P, Smith, M, Soares, M, Torres, A, Vieillard-Baron, A, Azoulay, E, Université Paris Diderot - Paris 7 (UPD7), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), University of Copenhagen = Københavns Universitet (KU), Erasmus University Medical Center [Rotterdam] (Erasmus MC), Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Azienda Ospedaliera Universitaria Santa Maria della Misericordia, Udine, Italy., Ghent University Hospital, Ghent, Belgium, The University of Washington, University of Sydney, Sydney, Australia., University of Toronto, Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Physiologie & médecine expérimentale du Cœur et des Muscles [U 1046] (PhyMedExp), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU), UCL Institute of Child Health and Great Ormond St Hospital, London, UK, Department of Intensive Care, Institute for Nutrition Research, Rabin Medical Center, Tel Aviv University [Tel Aviv], University College London Hospitals, D'Or Institute for Research and Education, Hospital Clinic of Barcelona, C, Service de réanimation medico-chirurgicale [CHU Raymond-Poincaré], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Ambroise Paré [AP-HP], Hospital Ambroise Paré, Viellard-Baron, A, Intensive Care, Internal Medicine, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), University of Copenhagen = Københavns Universitet (UCPH), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Tel Aviv University (TAU), and University College of London [London] (UCL)

Subjects
Critical Care, Process (engineering), [SDV]Life Sciences [q-bio], Negative binomial distribution, MEDLINE, Bibliometrics, Critical Care and Intensive Care Medicine, World Wide Web, 03 medical and health sciences, 0302 clinical medicine, Intensive care, Medicine, Humans, ComputingMilieux_MISCELLANEOUS, Actuarial science, downloads and citations, business.industry, 030208 emergency & critical care medicine, 3. Good health, 030228 respiratory system, Poster Presentation, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Septic Shock, Expert Panel, Specialized Medium, Improvement Process, Intensive Care Medicine, Journal Impact Factor, Periodicals as Topic, business
Abstract

Methods All papers accepted in 2012-2013 have been tracked through the Web-of-Science database for referencing and the Springer link statistics report for downloads from 01/01/2013 to 12/31/2014. Relative risk of being downloaded or cited one time are modeled with a multiple negative binomial regression. Variables tested were submitting country, manuscript category, open access, key-words, topics, number of author, and H-index of first and last author.

Published
2019
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3. Post cholecystectomy bile duct injury: early, intermediate or late repair with hepaticojejunostomy – an E-AHPBA multi-center study

Author

Rystedt, J.M.L., Kleeff, J., Salvia, R., Besselink, M.G., Prasad, R., Lesurtel, M., Sturesson, C., Abu Hilal, M., Aljaiuossi, A., Antonucci, A., Ardito, F., Ausania, F., Bernon, M., Berrevoet, F., Bjornsson, B., Bonsing, B.A., Boonstra, E.A., Bracke, B., Brusadin, R., Burda, L., Caraballo, M., Casellas-Robert, M., Coker, A., Davide, J., Gelder, A. de, Rose, A.M. de, Djokic, M., Dudek, K., Ekmekcigil, E., Filauro, M., Fulop, A., Gallagher, T.K., Gastaca, M., Gefen, R., Giuliante, F., Habibeh, H., Halle-Smith, J., Haraldsdottir, K.H., Hartman, V., Hauer, A., Hemmingsson, O., Hoskovec, D., Isaksson, B., Jonas, E., K.A., Klug, R., Krige, J., Lignier, D., Lindemann, J., Lopez-Lopez, V., Lucidi, V., Mabrut, J.Y., Mansson, C., Mieog, S., Mirza, D.F., Oldhafer, K.J., Omoshoro-Jones, J.A.O., Ortega-Torrecilla, N., Otto, W., Panaro, F., Pando, E., Paterna-Lopez, S., Pekmezci, S., Pesce, A., Porte, R.J., Poves, I., Calvo, M.P., Primavesi, F., Puleo, S., Recordare, A., Rizell, M., Roberts, K., Robles-Campos, R., Sanchiz-Cardenas, E., Sandstrom, P., Saribeyoglu, K., Schauer, M., Schreuder, M., Siriwardena, A.K., Smith, M.D., Silva, D.S., Sparrelid, E., Stattner, S., Stavrou, G.A., Straka, M., Stromberg, C., Sutcliffe, R.P., Szijarto, A., Taflin, H., Trotovsek, B., Gulik, T. van, Wallach, N., Zieniewicz, K., European-African HepatoPancreato, Skane University Hospital [Lund], Fachbereich Physik [Halle-Saale], Martin-Luther-Universität Halle Wittenberg (MLU), Azienda Ospedaliera Universitaria Integrata of Verona, University of Amsterdam [Amsterdam] (UvA), St James's University Hospital, Leeds Teaching Hospitals NHS Trust, Hôpital de la Croix-Rousse [CHU - HCL], Hospices Civils de Lyon (HCL), Karolinska University Hospital [Stockholm], University of Southampton, Policlinico di Monza, Partenaires INRAE, Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Catholic University, Rome, Italy, Complexo Hospitalario Universitario de Vigo, Ghent University Hospital, Linköping University (LIU), Universiteit Leiden [Leiden], University Medical Center Groningen [Groningen] (UMCG), Universiteit Antwerpen [Antwerpen], Universidad de Murcia, J. G. Mendel Cancer Center Novy Jicin, Universidad de Salamanca, Hospital Dr Josep Trueta de Girona, Izmir University, TURKEY, Faculdade de Medicina da Universidade do Porto (FMUP), Universidade do Porto, University of Ljubljana, University of Warsaw (UW), İZMİR EGE University Medical Faculty Hospital, Univeristà di Genova, Semmelweis University of Medicine [Budapest], University of Dublin, Universidad de Deusto [Bilbao] (DEUSTO), Universidad de Deusto (DEUSTO), Hospital Universitario Cruces = Cruces University Hospital, Hadassah Hebrew University Hospital, The Hebrew University of Jerusalem (HUJ), Catholic University of Rome, Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Queens Elizabeth Hospital [Birmingham], University of Iceland [Reykjavik], Community Hospital of horn, Umeå University, University Hospital Motol [Prague], Uppsala Universitet [Uppsala], University of Cape Town, Hadassah Hebrew University Medical Center [Jerusalem], Community Hospital Horn, CHU Amiens-Picardie, Vrije Universiteit Brussel (VUB), Université de Lyon, Asklepios Klinik Barmbek, University of Johannesburg (UJ), Vall d'Hebron University Hospital [Barcelona], Facultad de Medicina [Zaragoza], University of Zaragoza - Universidad de Zaragoza [Zaragoza], Cerrahpasa Medical Faculty, University of Catania [Italy], IMIM-Hospital del Mar, Generalitat de Catalunya, Innsbruck Medical University [Austria] (IMU), Unité Expérimentale Recherches Intégrées - Gotheron (UERI), Institut National de la Recherche Agronomique (INRA), University of Pristina-Kosovo, Peja/Pec Hospital, Sahlgrenska Academy at University of Gothenburg [Göteborg], Universidad de Málaga [Málaga] = University of Málaga [Málaga], University Hospital Düsseldorf, Vrije Universiteit Medical Centre (VUMC), Vrije Universiteit Amsterdam [Amsterdam] (VU), Manchester Royal Infirmary, University of Manchester [Manchester], Chris Hani Baragwanath Hospital, Centre Hospitalier Lyon Sud [CHU - HCL] (CHLS), European-African HepatoPancreato, Ege Üniversitesi, Groningen Institute for Organ Transplantation (GIOT), Surgery, AGEM - Digestive immunity, AGEM - Re-generation and cancer of the digestive system, CCA - Cancer Treatment and Quality of Life, and AGEM - Endocrinology, metabolism and nutrition

Subjects
INTRAOPERATIVE CHOLANGIOGRAPHY, Male, IMPACT, Settore MED/18 - CHIRURGIA GENERALE, medicine.medical_treatment, Jejunostomy, Hepatic Duct, Common, Comorbidity, 030230 surgery, 0302 clinical medicine, Cholangiography, Older patients, Hepatic Duct, Clinical endpoint, LAPAROSCOPIC CHOLECYSTECTOMY, COMPLICATIONS, OUTCOMES, medicine.diagnostic_test, Bile duct, Gastroenterology, Hepaticojejunostomy, Middle Aged, Common, 3. Good health, medicine.anatomical_structure, 030220 oncology & carcinogenesis, Female, Adult, medicine.medical_specialty, Bile duct injuries (BDI), CLASSIFICATION, Time-to-Treatment, Biliary injury, 03 medical and health sciences, Sex Factors, HEPATIC-ARTERY INJURY, medicine, MANAGEMENT, Humans, Cholecystectomy, Aged, Retrospective Studies, Hepatology, business.industry, [SDV.MHEP.HEG]Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology, BILIARY INJURY, Surgery, Multi center study, Concomitant, RISK-FACTORS, Human medicine, Bile Ducts, business
Abstract

13th World Biennial Congress of the International-Hepato-Pancreato-Biliary-Association (IHPBA) -- SEP 04-07, 2018 -- Geneva, SWITZERLAND, Ardito, Francesco/0000-0003-1596-2862; PESCE, ANTONIO MD/0000-0002-7560-551X; Gallagher, Tom/0000-0002-5765-2574; Bernon, Marc/0000-0002-7967-8548; Stattner, Stefan/0000-0002-5226-7597; GIULIANTE, FELICE/0000-0003-2087-2589; Omoshoro-Jones, Jones A. O./0000-0002-1071-298X; de Rose, Agostino Maria/0000-0003-3310-8088; Abu Hilal, Mohammed/0000-0002-3162-4639; Kleeff, Jorg/0000-0003-3432-6669; Prieto, Mikel/0000-0001-6662-4252; Stromberg, Cecilia/0000-0003-0843-7920, WOS: 000500283700006, PubMed: 31151812, Background: Treatment of bile duct injuries (BDI) during cholecystectomy depends on the severity of injury and the timing of diagnosis. Standard of care for severe BDIs is hepaticojejunostomy. the aim of this retrospective multi-center study was to assess the optimal timing for repair of BDI with hepaticojejunostomy. Methods: Members of the European-African HepatoPancreatoBiliary Association were invited to report all consecutive patients with hepaticojejunostomy after BDI from January 2000 to June 2016. Patients were stratified according to the timing of biliary reconstruction with hepaticojejunostomy: early (day 0-7), intermediate (1-6 weeks) and late (6 weeks-6 months). Primary endpoint was re-intervention >90 days after the hepaticojejunostomy and secondary endpoints were severe 90-day complications and liver-related mortality. Results: in total 913 patients from 48 centers were included in the analysis. in 401 patients (44%) the bile duct injury was diagnosed intraoperatively, and 126 patients (14%) suffered from concomitant vascular injury. in multivariable analysis the timing of hepaticojejunostomy had no impact on postoperative complications, the need for re-intervention after 90 days nor liver-related mortality. the rate of re-intervention more than 90 days after the hepaticojejunostomy was significantly increased in male patients but decreased in older patients. Severe co-morbidity increased the risk for liver-related mortality (HR 3.439; CI 1.37-8.65; p = 0.009). Conclusion: After BDI occurring during cholecystectomy, the timing of biliary reconstruction with hepaticojejunostomy did not have any impact on severe postoperative complications, the need for re-intervention or liver-related mortality. Individualised treatment after iatrogenic bile duct injury is still advisable., Int Hepato Pancreato Biliary Assoc

Published
2019
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4. Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA) (vol 11, 33, 2016)

Author

Sartelli, M., Weber, D. G., Ruppe, E., Bassetti, M., Wright, B. J., Ansaloni, L., Catena, F., Coccolini, F., Abu-Zidan, F. M., Coimbra, R., Moore, E. E., Moore, F. A., Maier, R. V., De Waele, J. J., Kirkpatrick, A. W., Griffiths, E. A., Eckmann, C., Brink, A. J., Mazuski, J. E., May, A. K., Sawyer, R. G., Mertz, D., Montravers, P., Kumar, A., Roberts, J. A., Vincent, L., Watkins, R. R., Lowman, W., Spellberg, B., Abbott, I. J., Adesunkanmi, A. K., Al-Dahir, S., Al-Hasan, M. N., Agresta, F., Althani, A. A., Ansari, S., Ansumana, R., Augustin, G., Bala, M., Balogh, Z. J., Baraket, O., Bhangu, A., Beltrán, Anna Maria, Bernhard, M., Biffl, W. L., Boermeester, M. A., Brecher, S. M., Cherry-Bukowiec, J. R., Buyne, O. R., Cainzos, M. A., Cairns, K. A., Camacho-Ortiz, A., Chandy, S. J., Jusoh, A. Che, Chichom-Mefire, A., Colijn, C., Corcione, F., Cui, Y., Curcio, D., Delibegovic, S., Demetrashvili, Z., De Simone, B., Dhingra, S., Diaz, J. J., Di Carlo, I., Dillip, A., Di Saverio, S., Doyle, M. P., Dorj, G., Dogjani, A., Dupont, H., Eachempati, S. R., Enani, M. A., Egiev, V. N., Elmangory, M. M., Ferrada, P., Fitchett, J. R., Fraga, G. P., Guessennd, N., Giamarellou, H., Ghnnam, W., Gkiokas, G., Goldberg, S. R., Gomes, C. A., Gomi, H., Guzman-Blanco, M., Haque, M., Hansen, S., Hecker, A., Heizmann, W. R., Herzog, T., Hodonou, A. M., Hong, S. K., Kafka-Ritsch, R., Kaplan, L. J., Kapoor, G., Karamarkovic, A., Kees, M. G., Kenig, J., Kiguba, R., Kim, P. K., Kluger, Y., Khokha, V., Koike, K., Kok, K. Y., Kong, V., Knox, M. C., Inaba, K., Isik, A., Iskandar, K., Ivatury, R. R., Labbate, M., Labricciosa, F. M., Laterre, P. F., Latifi, R., Lee, J. G., Lee, Y. R., Leone, M., Leppaniemi, A., Li, Y., Liang, S. Y., Loho, T., Maegele, M., Malama, S., Marei, H. E., Martin-Loeches, I., Marwah, S., Massele, A., McFarlane, M., Melo, R. B., Negoi, I., Nicolau, D. P., Nord, C. E., Ofori-Asenso, R., Omari, A. H., Ordonez, C. A., Ouadii, M., Pereira Junior, G. A., Piazza, D., Pupelis, G., Rawson, T. M., Rems, M., Rizoli, S., Rocha, C., Sakakushev, B., Sanchez-Garcia, M., Sato, N., Segovia Lohse, H. A., Sganga, G., Siribumrungwong, B., Shelat, V. G., Soreide, K., Soto, R., Talving, P., Tilsed, J. V., Timsit, J. F., Trueba, G., Trung, N. T., Ulrych, J., Van Goor, H., Vereczkei, A., Vohra, R. S., Wani, I., Uhl, W., Xiao, Y., Yuan, K. C., Zachariah, S. K., Zahar, J. R., Zakrison, T. L., Corcione, A., Melotti, R. M., Viscoli, C., Viale, P., Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Universidade de Aveiro, Laboratoire matériaux et microélectronique de Provence (L2MP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur de Côte d'Ivoire, Réseau International des Instituts Pasteur (RIIP), National Defence University of Malaysia [Kuala Lumpur], Max Planck Institute for the Physics of Complex Systems (MPI-PKS), Max-Planck-Gesellschaft, Center for Plant Molecular Biology, Plant Physiology, and Biophysical Chemistry, University of Tübingen, Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR48, Institut des sciences biologiques (INSB-CNRS)-Institut des sciences biologiques (INSB-CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica 'Giuseppe Occhialini' = Department of Physics 'Giuseppe Occhialini' [Milano-Bicocca], Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Atmospheric and Environmental Research, Inc. (AER), Zhejiang University, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], INSB-INSB-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), and COMBE, Isabelle

Subjects
[SDV.MHEP] Life Sciences [q-bio]/Human health and pathology, Carbapenems, Antimicrobial Resistance, Invasive Candidiasis, Methicillin Resistant Staphylococcus Aureus, Tigecycline, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients.The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance.The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria.An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs.

Published
2017
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5. Sounding Titan's Lakes and Seas: Bathymetry, Composition, and Role in the Hydrologic Cycle

Author

Hayes, Alexander, Mastrogiuseppe, Marco, Lunine, Jonathan I., Poggiali, Valerio, Lorenz, Ralph, Le Gall, Alice, Mitchell, Karl L., Department of Astronomy [Ithaca], Cornell University [New York], Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), ESTER - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), PLANETO - LATMOS, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; One of the most surprising discoveries of the Cassini Solstice Mission is the microwave transparency of Titan's lakes and seas. Coherent processing of altimetry echoes acquired over Ligeia Mare in May 2013 revealed bottom reflections and allowed construction of a bathymetric profile as well as an estimation of the liquid loss tangent. Following the successful detection of subsurface echoes at Ligeia, the RADAR team organized a campaign to acquire altimetry over the remaining Mare. Altimetry over Kraken and Punga Maria were obtained in August 2014 and January 2015, respectively, and also show detectable subsurface echoes. Using new analysis techniques, subsurface returns were also recovered from data acquired over Ontario Lacus in 2008. The final Titan flyby (T126, April 2017) will acquire altimetry over several of the smaller lakes in Titan's north, permitting comparative studies between the Mare and lakes. In this presentation, we will report on the latest results from this ongoing campaign.Assuming a ternary composition of CH4, C2H6, and N2, the best-fit loss tangent at Ligeia Mare is consistent with 71% CH4, 12% C2H6, and 17% N2 by volume. The best-fit loss tangent Ontario Lacus is consistent with 47% CH4, 40% C2H6, and 13% N2. The higher loss tangent at Ontario Lacus could result from an increased abundance of more involatile hydrocarbons and/or nitriles; these species could be concentrated as a consequence of orbitally-driven insolation cycles that may have slowly transported volatile components (methane/ ethane) to the north over the past several tens of millennia. Initial analysis of Kraken and Punga Maria suggest liquid absorptivity similar to Ligeia Mare. In total, the bathymetric results suggest that the total volume of Titan's lakes and seas is >70,000 km3. If this liquid were evenly spread across the surface it would be equivalent to a global ocean depth of 1 m. This is equivalent to 300 times the mass of Earth's proven natural gas reserves. Unlike Earth, where the total water content in the atmosphere (1.29x104 km3) is only a fraction of the surficial reservoir (1.35x109 km3), the moisture content in Titan's atmosphere is approximately seven times larger than the volume found in its lakes and seas.

Published
2016

6. The Bathymetry and Composition of Titan’s Lakes and Seas

Author

Hayes, Alexander G., Mastrogiuseppe, Marco, Lumine, J. I., Poggiali, Valerio, Lorenz, R. D., Mitchell, K. M., Malaska, Michael J., Le Gall, Alice, Center for Radiophysics and Space Research [Ithaca] (CRSR), Cornell University [New York], Cornell Center for Astrophysics and Planetary Science (CCAPS), Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ESTER - LATMOS, and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; Despite pre-launch predictions that hydrocarbon liquids would be transparent to Cassini's 13.8 GHz radar [1] and that the radar's altimetry mode might be used as a sounder to probe Titan's liquids [2], experiments using liquefied natural gas by Paillou et al. [3] suggested that penetration would be significantly shallower than the altimeter's 35 m range resolution. Nevertheless, Mastrogiuseppe et al. [4] successfully detected subsurface reflections in altimetry echoes acquired over Ligeia Mare in May 2013 (Figure 1). Coherent processing of these echoes revealed the bottom reflection and allowed construction of a bathyme-try profile as well as an estimation of the liquid loss tangent from the relative variation in subsurface power. Subsequent altimetry observations of Kraken and Punga Maria obtained in August 2014 and January 2015, respectively, also showed detectable subsurface echoes. After applying these new techniques, subsur-face echoes were also observed in altimetry data acquired over Ontario Lacus in 2008. In this proceeding, we will report on the latest results from the analyses of these altimetry passes

Published
2016

7. Cassini RADAR Observations of Saturn's Largest Moon, Titan

Author

Hayes, Alexander, Mastrogiuseppe, Marco, Lunine, Jonathan, Lorenz, Ralph, Wall, Stephen, Stiles, Bryan, Kirk, Randolph L., Elachi, Charles, Hofgartner, Jason, Birch, Samuel, Le Gall, Alice, Poggiali, Valerio, Zebker, Howard, Department of Astronomy [Ithaca], Cornell University [New York], Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), United States Geological Survey [Reston] (USGS), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Electrical Engineering [Stanford], Stanford University, and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; The Cassini RADAR is a versatile instrument capable of operating in imaging, altimetry, scatterometry, radiometry, and, most recently, sounding modes. Despite vastly different material properties and environmental conditions, Titan’s methane-based hydrologic system drives climatic and geologic processes that result in morphologic features with striking similarity to terrestrial counterparts, including vast equatorial dune fields, well-organized channel networks that route material through erosional and depositional landscapes defining source-to-sink sediment transport systems, and, perhaps most astonishingly, lakes and seas filled with liquid hydrocarbons.Using its various operating modes, the Cassini RADAR has provided a wealth of information regarding Titan’s active surface-atmosphere system. In Synthetic Aperture Radar (SAR) mode, the RADAR has unveiled Titan’s surface by producing backscatter maps with pixel scales of ~300 m. In altimetry mode, the RADAR has shown the elevation profile of surface features, including the liquid elevation of Titan’s lakes and seas, revealed the roughness characteristics of the surface, and constrained the global shape. Most recently, the altimetry mode has doubled as a radar sounder that has successfully probed the depth and absorptivity of the lakes and seas. Data from the scatterometry and radiometry modes have been used to constrain material properties, including dielectric constants and volume scattering fractions, surface texture, and derive seasonal and diurnal temperature variations. Collectively, these datasets have revealed Titan’s strange yet familiar nature, and demonstrated that it is one of the most compelling targets in our solar system. During our presentation, we will summarize these capabilities and review some of the most specular discoveries made by the Cassini RADAR.

Published
2015

8. The case for water ice in Titan’s near subsurface

Author

Le Gall, Alice, Janssen, Michael, Malaska, Michael, Lopes, Rosaly, Solomonidou, Anezina, Lorenz, Ralph, Neish, Catherine, Radebaugh, Jani, Encrenaz, Pierre, Mastrogiuseppe, Marco, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Florida Institute of Technology [Melbourne], Department of Geological Sciences [BYU], Brigham Young University (BYU), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), California Institute of Technology (CALTECH)-NASA, École normale supérieure - Paris (ENS Paris), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], and Cardon, Catherine

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; Titan’s deep crust is thought to be made of water ice in its solid form or as clathrate hydrates. However, its actual expression on the surface has proven ambiguous. Only regions possibly enriched in water ice have been identified by the Visible and Infrared Mapping Spectrometer (VIMS) on board Cassini. Overall, the surface of Titan seems to be covered by a sedimentary layer of solid organics, likely originating from methane photolysis in the atmosphere. Nevertheless, the thickness of this layer may vary across Titan and the best chance for detecting water ice is in the microwave region where greater depths into the surface are probed. Considering both the active and passive data collected by the RADAR on board Cassini, we will show that the presence of water ice in the near subsurface is strongly indicated by the high degree of volume scattering observed in radar-bright/low-emissive regions (mountain-like terrains) comprising ~ 10% of Titan’s surface. The rims of several craters also demonstrate unique characteristics in the microwave that suggest the presence of water ice. The impacts that caused these features can be expected to expose material from the deep subsurface, certainly bringing large quantities of ice to the surface. We will discuss the implications of these findings.

Published
2015

9. An Overview of the Bathymetry and Composition of Titan’s Hydrocarbon Seas from the Cassini RADAR Altimeter

Author

Mastrogiuseppe, Marco, Hayes, Alexander, Lunine, Jonathan, Poggiali, Valerio, Seu, Roberto, Hofgartner, Jason, Lorenz, Ralph, Le Gall, Alice, Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Department of Astronomy [Ithaca], Cornell University [New York], Dipartimento INFOCOM [Roma], Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), ESTER - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), PLANETO - LATMOS, and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome]

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract

International audience; The Cassini RADAR’s altimetry mode has been successfully used for probing the depth and composition of Titan’s hydrocarbons seas. In May 2013, during the spacecraft’s 91stflyby of Titan (T91), the instrument demonstrates its capabilities as a radar sounder, presenting a unique opportunity to constrain direct measurements of the depth and composition of Titan’s second largest sea, Ligeia Mare. Later, observations of Kraken Mare and Punga Mare were planned and executed in August 2014 (T104) and January 2015 (T108), respectively. While most of the seafloor was not detected at Kraken, suggesting the sea was either too deep or too absorptive in these areas to observe a return from the seafloor, shallow areas near Moray Sinus did return subsurface detections. At Punga Mare, a clear detection of the subsurface was observed with a maximum depth of 120 m along the interrogated track of the sea. We will present an analysis of all three altimetric observations of Titan’s mare, as well a re-analysis of altimetry data acquired over southern Ontario Lacus. Depths measurements and liquid composition are obtained using a novel technique which makes use of radar simulations and Monte Carlo based inversions. Finally, we will show that the estimates obtained from the direct measurements described above can be used along with the RADAR’s active (i.e. Synthetic Aperture Radar) and passive (Radiometry) modes to generate bathymetry maps of areas not observed by altimetry.

Published
2015

10. Composition, seasonal change and bathymetry of Ligeia Mare, Titan, derived from its 2.2-cm thermal emission

Author

Le Gall, Alice, Malaska, Michael, Lorenz, Ralph, Janssen, Michael, Tokano, Tetsuya, Hayes, Alexander, Lunine, Jonathan, Veyssière, Gaëlle, Mastrogiuseppe, Marco, Karatekin, Ozgur, Encrenaz, Pierre, Cardon, Catherine, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Institut für Geophysik und Meteorologie [Köln], Universität zu Köln, Department of Astronomy [Ithaca], Cornell University [New York], Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Royal Observatory of Belgium [Brussels] (ROB), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), NASA-California Institute of Technology (CALTECH), Universität zu Köln = University of Cologne, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), and École normale supérieure - Paris (ENS-PSL)

Subjects
[SDU.ASTR.IM] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.SR] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract

International audience; For the last 10 years, the Cassini RADAR has been exploring Saturn’s moon Titan, the only planetary body besides Earth whose surface presently exhibits significant accumulations of liquids in the forms of lakes and seas. In particular, the passive Radiometer that is incorporated in this instrument has been recording the 2.2 cm-wavelength thermal emission from Titan’s three seas. Radiometry observations provide new information beyond the active radar reflection data. In this paper, we analyze the radiometry observations collected from Feb. 2007 to July 2013 over one of these seas, Ligeia Mare, with the goal of providing constrains on its liquid composition, seafloor nature, bathymetry, and dynamics. In light of the two-layer model we have developed for this analysis, we find that the dielectric constant of the sea liquid is most likely smaller than 1.8, suggesting that the composition of Ligeia Mare is dominated by liquid methane rather than liquid ethane (although a ternary methane-ethane-nitrogen mixture cannot be ruled out). This result is further supported by the value we infer for the liquid loss tangent of 3-5×10-5. This value is in agreement with the one first published by Mastrogiuseppe et al. (2014) based on active radar observation. A high methane concentration suggests that Ligeia Mare is either a sea from which ethane has been removed by crustal interaction, or a sea primarely fed by methane-rich precipitation, or both. For the seafloor, a dielectric constant of 2.6-2.9±0.9 is determined. Though this result is not very constraining, we favor a scenario where the floor of Ligeia Mare is covered by a sludge of compacted and possibly nitrile-rich organic material formed by the deposition of photochemical haze or by rain-washing of the nearby shores. These results are then used to convert the radiometry mosaic of Ligeia Mare into a qualitative low-resolution bathymetry map. Lastly, we establish limits on the physical temperature variation of the sea between Feb. 2007 to July 2013, namely less than 2 K, providing a constraint on the relative amounts of solar heating and evaporative cooling currently being explored in ocean circulation models.

Published
2015

11. Composition and bathymetry of Ligeia Mare, Titan, derived from its 2.2-cm wavelength thermal microwave emission

Author

Le Gall, Alice, Janssen, Michael, Mastrogiuseppe, Marco, Hayes, Alexander, Lorenz, Ralph, Encrenaz, Pierre, Malaska, Michael, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ESTER - LATMOS, Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Department of Astronomy [Ithaca], Cornell University [New York], Johns Hopkins University (JHU), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), NASA-California Institute of Technology (CALTECH), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), École normale supérieure - Paris (ENS-PSL), and Cardon, Catherine

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; In May 2013, the bottom of Ligeia Mare (LM), Titan, was detected in the active altimetry mode of the Cassini RADAR at a maximum depth of 160 m (Mastroguiseppe et al., 2014). This was the first and, so far, only detection of the floor of an extraterrestrial sea. The difference of amplitude of the surface and bottom echoes was also investigated in order to evaluate losses by absorption in the liquid layer. In this paper, we analyze the passive radiometry data that were acquired concurrently with the active data, in order to provide an independent estimate of the liquid loss tangent and to determine the dielectric constant of both the liquid and the seafloor. We then used these results to convert the radiometry mosaic of LM into a low-resolution bathymetry map.For the last 10 years, the passive radiometer incorporated in the Cassini RADAR has been observing the 2.2-cm wavelength thermal microwave emission from Titan. Its calibration has been recently refined to an unprecedented accuracy of

Published
2014

12. Modeling and Observing the Role of Wind-Waves in Lake-Climate Interactions on Titan using the T104 Flyby of Kraken Mare

Author

Hayes, Alexander, Lorenz, Ralph, Zebker, Howard, Donelan, Mark, Karatekin, Ozgur, Mastrogiuseppe, Marco, Le Gall, Alice, Hofgartner, Jason, Encrenaz, Pierre, Poggiali, Valerio, Department of Astronomy [Ithaca], Cornell University [New York], Johns Hopkins University (JHU), Department of Electrical Engineering [Stanford], Stanford University, Rosenstiel School of Marine and Atmospheric Science (RSMAS), University of Miami [Coral Gables], Royal Observatory of Belgium [Brussels] (ROB), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ESTER - LATMOS, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), École normale supérieure - Paris (ENS Paris), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], and Cardon, Catherine

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience; Oceanography is no longer just an Earth Science. Standing bodies of liquid that interact with both atmospheric and surface reservoirs are known to exist on Titan, and are thought to have existed on early Mars. The exchange of heat, moisture, and momentum between lakes/seas and the atmosphere are of fundamental importance to the hydrologic systems of all three bodies. The generation and propagation of wind-waves, and their consequent shoreline erosion, are key factors in air-sea-surface exchange. Titan, in particular, offers a laboratory in which to understand these processes at a more fundamental level. Much of the parameterization for wave models on Earth are empirical, despite laboratory studies that have demonstrated wave growth depends on both gravity and fluid properties. Titan’s exotic environment ensures that even rudimentary measurements of wave generation will provide valuable data to anchor physical models. Furthermore, in the presence of wind waves, Cassini can be used as an anemometer to measure wind speeds over hydrocarbon liquids.Herein, we will report on the results of the Aug 21st altimetry observation over Titan’s largest sea, Kraken Mare, and interpret them in the context of wave activity and composition (from passive radiometry). On Earth, it is rare to observe a body of water whose surface is not disturbed by some form of wave activity. On Titan, Cassini observations through the end of its Equinox Mission in Dec 2010 showed no indication of waves. These observations are intriguing given the predominance of aeolian features at equatorial latitudes and have been attributed to the light winds predicted during the Titan winter. More recently, however, the previous series of upper limits and non-detections are giving way to indications that the expected freshening of winds in northern summer may be causing sporadic ruffling of the sea surfaces. Specifically, apparent sunglints offset from the geometric specular point has been observed by VIMS in Punga Mare and a transient radar signature has been observed over the surface of Ligeia Mare. SAR images also reveal morphologies consistent with secondary coastlines, most notably at Ontario Lacus and Ligeia Mare. In addition to the altimetry of Kraken, we will also discuss the potential role of wind-waves in shaping coastal morphologies observed in SAR images.

Published
2014

13. Allenylidene to Indenylidene Rearrangement in Cationic p-Cymene Ruthenium(II) Complexes: Solvent, Counteranion, and Substituent Effects in the Key Step toward Catalytic Olefin Metathesis

Author

Pierre H. Dixneuf, Mauro Bassetti, Arianna Antonucci, Christian Bruneau, Chiara Pasquini, Universita 'La Sapienza' Roma (Istituto CNR), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)

Subjects
p-Cymene, allenylidene, Stereochemistry, Substituent, chemistry.chemical_element, 010402 general chemistry, Metathesis, 01 natural sciences, Medicinal chemistry, Catalysis, Inorganic Chemistry, chemistry.chemical_compound, ruthenium complexes, olefin metathesis, Physical and Theoretical Chemistry, Olefin fiber, catalysis, 010405 organic chemistry, Organic Chemistry, Cationic polymerization, [CHIM.CATA]Chemical Sciences/Catalysis, 0104 chemical sciences, Ruthenium, Solvent, chemistry, kinetics
Abstract

International audience; The reaction of [(η6-p-cymene)RuCl(PCy3)][OTf] with Ph2C(OH)C≡CH, at rt in benzene-d6 or in dichloromethane-d2, affords the allenylidene complex [(η6-p-cymene)RuCl(═C═C═CPh2)PCy3][OTf] ({4a}), which is used in situ as a catalyst for the ring-closing metathesis (RCM) reaction of diallyltosylamide. A kinetic study is performed by 1H NMR spectroscopy in benzene-d6 and dichloromethane-d2. The rates of the olefin metathesis process increase with the concentration of the ruthenium complex, but are independent of the olefin concentration, due to rate-determining transformation of the allenylidene complex. The TOF values are higher in benzene-d6 than in dichloromethane-d2. The spontaneous or thermally induced transformations of the allenylidene complexes [(η6-p-cymene)RuCl(═C═C═CAr2)PR3][X] (Ar = Ph, X = CF3SO3−(OTf) ({4a}), BF4− ({4b}), PF6− ({4c}), SbF6− ({4d}) ; X = OTf, Ar = p-MeOC6H4 ({4e}), Ar = p-ClC6H4 ({4f}), Ar = p-FC6H4 ({4g})), prepared in situ from the cationic precursors [(η6-p-cymene)RuCl(PCy3)][X] (X = OTf (8a), BF4− (8b), PF6− (8c), SbF6− (8d) and the propargylic alcohols (4-YC6H4)2C(OH)C≡CH (Y = H, OMe, Cl, F), are studied by UV−visible spectroscopy by following the disappearance of the allenylidene moiety Ru═C═C═CAr2. The allenylidene to indenylidene rearrangement involves attack by the ortho-carbon of the aryl rings to the electrophilic allenylidene Cα, to form an intermediate arenium ion, and H-transfer from aryl to Cβ. Faster rates are observed in benzene than in dichloromethane in all cases. The first-order rate constants, kobs, for complexes 4a−d (Ar = Ph) depend on the counteranion nature and decrease in the order BF4− > OTf PF6− > SbF6− in benzene, while they are insensitive to the counteranion nature in dichloromethane. Measurements performed at different temperatures afford the activation parameters ΔH‡ = 22 ± 2 kcal mol−1 and ΔS‡ = −1 ± 5 cal mol−1 K−1 for complex {4a} at 18−50 °C and ΔH‡ = 24 ± 1 kcal mol−1 and ΔS‡ = 1 ± 1 cal mol−1 K−1 for complex {4e} at 25−55 °C. The values of activation entropy, which do not support a rate-determining phosphine dissociation step, and the rate effects of the aryl p-substituents are consistent with an early transition state in the C−C bond forming step of the ring-closing process. Rate differences between benzene and dichloromethane are discussed in terms of counteranion interactions in the less polar aromatic solvent. The rates of the allenylidene transformation affect directly the rates of the RCM reaction, as indicated by parallel solvent, proton, counteranion, and aryl substituent effects in the two processes, thus establishing the role of allenylidene−indenylidene rearrangement in the acid-free olefin metathesis.

Published
2010
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