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1. ExoClock Project III: 450 new exoplanet ephemerides from ground and space observations

Author

Kokori, A., Tsiaras, A., Edwards, B., Jones, A., Pantelidou, G., Tinetti, G., Bewersdorff, L., Iliadou, A., Jongen, Y., Lekkas, G., Nastasi, A., Poultourtzidis, E., Sidiropoulos, C., Walter, F., Wünsche, A., Abraham, R., Agnihotri, V. K., Albanesi, R., Arce-Mansego, E., Arnot, D., Audejean, M., Aumasson, C., Bachschmidt, M., Baj, G., Barroy, P. R., Belinski, A. A., Bennett, D., Benni, P., Bernacki, K., Betti, L., Biagini, A., Bosch, P., Brandebourg, P., Brát, L., Bretton, M., Brincat, S. M., Brouillard, S., Bruzas, A., Bruzzone, A., Buckland, R. A., Caló, M., Campos, F., Carreno, A., Rodrigo, J. -A. Carrion, Casali, R., Casalnuovo, G., Cataneo, M., Chang, C. -M., Changeat, L., Chowdhury, V., Ciantini, R., Cilluffo, M., Coliac, J. -F., Conzo, G., Correa, M., Coulon, G., Crouzet, N., Crow, M. V., Curtis, I., Daniel, D., Dawes, S., Dauchet, B., Deldem, M., Deligeorgopoulos, D., Dransfield, G., Dymock, R., Eenmäe, T., Evans, P., Esseiva, N., Falco, C., Farfán, R. G., Fernández-Lajús, E., Ferratfiat, S., Ferreira, S. L., Ferretti, A., Fiołka, J., Fowler, M., Futcher, S. R., Gabellini, D., Gainey, T., Gaitan, J., Gajdoš, P., García-Sánchez, A., Garlitz, J., Gillier, C., Gison, C., Horta, F. Grau, Grivas, G., Gonzales, J., Gorshanov, D., Guerra, P., Guillot, T., Haswell, C. A., Haymes, T., Hentunen, V. -P., Hills, K., Hose, K., Humbert, T., Hurter, F., Hynek, T., Irzyk, M., Jacobsen, J., Jannetta, A. L., Johnson, K., Jóźwik-Wabik, P., Kaeouach, A. E., Kang, W., Kiiskinen, H., Kim, T., Kivila, Ü., Koch, B., Kolb, U., Kučáková, H., Lai, S. -P., Laloum, D., Lasota, S., Lewis, L. A., Liakos, G. -I., Libotte, F., Lopresti, C., Lomoz, F., Majewski, R., Malcher, A., Mallonn, M., Mannucci, M., Marchini, A., Mari, J. -M., Marino, A., Marino, G., Mario, J. -C., Marquette, J. -B., Martínez-Bravo, F. A., Mašek, M., Matassa, P., Michel, P., Michelet, J., Miller, M., Miny, E., Mollier, T., Molina, D., Monteleone, B., Montigiani, N., Morales-Aimar, M., Mortari, F., Morvan, M., Mugnai, L. V., Murawski, G., Naponiello, L., Naves, R., Naudin, J. -L., Néel, D., Neito, R., Neveu, S., Noschese, A., Öğmen, Y., Ohshima, O., Orbanic, Z., Pace, E. P., Pantacchini, C., Paschalis, N. I., Pereira, C., Peretto, I., Perroud, V., Phillips, M., Pintr, P., Pioppa, J. -B., Plazas, J., Poelarends, A. J., Popowicz, A., Purcell, J., Quinn, N., Raetz, M., Rees, D., Regembal, F., Rocchetto, M., Rocci, P. -F., Rockenbauer, M., Roth, R., Rousselot, L., Rubia, X., Ruocco, N., Russo, E., Salisbury, M., Salvaggio, F., Santos, A., Savage, J., Scaggiante, F., Sedita, D., Shadick, S., Silva, A. F., Sioulas, N., Školník, V., Smith, M., Smolka, M., Solmaz, A., Stanbury, N., Stouraitis, D., Tan, T. -G., Theusner, M., Thurston, G., Tifner, F. -P., Tomacelli, A., Tomatis, A., Trnka, J., Tylšar, M., Valeau, P., Vignes, J. -P., Villa, A., Sureda, A. Vives, Vora, K., Vrašťák, M., Walliang, D., Wenzel, B., Wright, D. E., Zambelli, R., Zhang, M., and Zíbar, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

The ExoClock project has been created with the aim of increasing the efficiency of the Ariel mission. It will achieve this by continuously monitoring and updating the ephemerides of Ariel candidates over an extended period, in order to produce a consistent catalogue of reliable and precise ephemerides. This work presents a homogenous catalogue of updated ephemerides for 450 planets, generated by the integration of $\sim$18000 data points from multiple sources. These sources include observations from ground-based telescopes (ExoClock network and ETD), mid-time values from the literature and light-curves from space telescopes (Kepler/K2 and TESS). With all the above, we manage to collect observations for half of the post-discovery years (median), with data that have a median uncertainty less than one minute. In comparison with literature, the ephemerides generated by the project are more precise and less biased. More than 40\% of the initial literature ephemerides had to be updated to reach the goals of the project, as they were either of low precision or drifting. Moreover, the integrated approach of the project enables both the monitoring of the majority of the Ariel candidates (95\%), and also the identification of missing data. The dedicated ExoClock network effectively supports this task by contributing additional observations when a gap in the data is identified. These results highlight the need for continuous monitoring to increase the observing coverage of the candidate planets. Finally, the extended observing coverage of planets allows us to detect trends (TTVs - Transit Timing Variations) for a sample of 19 planets. All products, data, and codes used in this work are open and accessible to the wider scientific community., Comment: Recommended for publication to ApJS (reviewer's comments implemented). Main body: 13 pages, total: 77 pages, 7 figures, 7 tables. Data available at http://doi.org/10.17605/OSF.IO/P298N

Published
2022
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2. ExoClock project II: A large-scale integrated study with 180 updated exoplanet ephemerides

Author

Kokori, A., Tsiaras, A., Edwards, B., Rocchetto, M., Tinetti, G., Bewersdorff, L., Jongen, Y., Lekkas, G., Pantelidou, G., Poultourtzidis, E., Wünsche, A., Aggelis, C., Agnihotri, V. K., Arena, C., Bachschmidt, M., Bennett, D., Benni, P., Bernacki, K., Besson, E., Betti, L., Biagini, A., Brandebourg, P., Bretton, M., Brincat, S. M., Caló, M., Campos, F., Casali, R., Ciantini, R., Crow, M. V., Dauchet, B., Dawes, S., Deldem, M., Deligeorgopoulos, D., Dymock, R., Eenmäe, T., Evans, P., Esseiva, N., Falco, C., Ferratfiat, S., Fowler, M., Futcher, S. R., Gaitan, J., Horta, F. Grau, Guerra, P., Hurter, F., Jones, A., Kang, W., Kiiskinen, H., Kim, T., Laloum, D., Lee, R., Lomoz, F., Lopresti, C., Mallonn, M., Mannucci, M., Marino, A., Mario, J. -C., Marquette, J. -B., Michelet, J., Miller, M., Mollier, T., Molina, D., Montigiani, N., Mortari, F., Morvan, M., Mugnai, L. V., Naponiello, L., Nastasi, A., Neito, R., Pace, E., Papadeas, P., Paschalis, N., Pereira, C., Perroud, V., Phillips, M., Pintr, P., Pioppa, J. -B., Popowicz, A., Raetz, M., Regembal, F., Rickard, K., Roberts, M., Rousselot, L., Rubia, X., Savage, J., Sedita, D., Shave-Wall, D., Sioulas, N., Školník, V., Smith, M., St-Gelais, D., Stouraitis, D., Strikis, I., Thurston, G., Tomacelli, A., Tomatis, A., Trevan, B., Valeau, P., Vignes, J. -P., Vora, K., Vrašťák, M., Walter, F., Wenzel, B., Wright, D. E., and Zíbar, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The ExoClock project is an inclusive, integrated, and interactive platform that was developed to monitor the ephemerides of the Ariel targets to increase the mission efficiency. The project makes the best use of all available resources, i.e., observations from ground telescopes, mid-time values from the literature and finally, observations from space instruments. Currently, the ExoClock network includes 280 participants with telescopes capable of observing 85\% of the currently known Ariel candidate targets. This work includes the results of $\sim$1600 observations obtained up to the 31st of December 2020 from the ExoClock network. These data in combination with $\sim$2350 mid-time values collected from the literature are used to update the ephemerides of 180 planets. The analysis shows that 40\% of the updated ephemerides will have an impact on future scheduling as either they have a significantly improved precision, or they have revealed biases in the old ephemerides. With the new observations, the observing coverage and rate for half of the planets in the sample has been doubled or more. Finally, from a population perspective, we identify that the differences in the 2028 predictions between the old and the new ephemerides have an STD that is double what is expected from gaussian uncertainties. These findings have implications for planning future observations, where we will need to account for drifts potentially greater than the prediction uncertainties. The updated ephemerides are open and accessible to the wider exoplanet community both from our Open Science Framework (OSF) repository and our website., Comment: 9 pages (47 with appendices and references), 8 figures, 2 tables. Submitted to ApJS. Revised based on the reviewer's comments

Published
2021
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3. A new method for unveiling Open Clusters in Gaia: new nearby Open Clusters confirmed by DR2

Author

Castro-Ginard, A., Jordi, C., Luri, X., Julbe, F., Morvan, M., Balaguer-Núñez, L., and Cantat-Gaudin, T.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

The publication of the Gaia Data Release 2 (Gaia DR2) opens a new era in Astronomy. It includes precise astrometric data (positions, proper motions and parallaxes) for more than $1.3$ billion sources, mostly stars. To analyse such a vast amount of new data, the use of data mining techniques and machine learning algorithms are mandatory. The search for Open Clusters, groups of stars that were born and move together, located in the disk, is a great example for the application of these techniques. Our aim is to develop a method to automatically explore the data space, requiring minimal manual intervention. We explore the performance of a density based clustering algorithm, DBSCAN, to find clusters in the data together with a supervised learning method such as an Artificial Neural Network (ANN) to automatically distinguish between real Open Clusters and statistical clusters. The development and implementation of this method to a $5$-Dimensional space ($l$, $b$, $\varpi$, $\mu_{\alpha^*}$, $\mu_\delta$) to the Tycho-Gaia Astrometric Solution (TGAS) data, and a posterior validation using Gaia DR2 data, lead to the proposal of a set of new nearby Open Clusters. We have developed a method to find OCs in astrometric data, designed to be applied to the full Gaia DR2 archive., Comment: 18 pages, accepted by Astronomy and Astrophysics (A&A) the 11th June, 2018

Published
2018
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4. Erratum: Consortium biology in immunology: The perspective from the Immunological Genome Project

Author

Benoist, C, Lanier, L, Merad, M, Mathis, D, Ericson, J, Painter, M, Davis, S, Laplace, C, Hyatt, G, Paik, H, Rothamel, K, Cruse, R, Doran, G, Heng, T, Asinovski, N, Ortiz-Lopes, A, Ergun, A, Gray, D, Wakamatsu, E, Hill, J, Mingueneau, M, Cipolletta, D, Yoshida, H, Cohen, N, Kim, E, Brennan, P, Lynch, L, Brenner, M, Costello, J, Collins, JJ, Blair, D, Dustin, M, Knell, J, Yang, E, Best, A, Shaw, L, Doedens, A, Goldrath, A, Shinton, S, Zhou, Y, Hardy, R, Jojic, V, Mostafavi, S, Koller, D, Jianu, R, Laidlaw, D, Bezman, N, Sun, J, Zhu, Y, Hendricks, D, Kamimura, Y, Min-Oo, G, Morvan, M, Nabekura, T, Lam, V, Kim, C, Greter, M, Helft, J, Chow, A, Bogunovic, M, Mortha, A, Price, J, Hashimoto, D, Miller, J, Sathe, P, Chudnovskiy, A, Lavin, Y, Idoyaga, J, Gautier, E, Jakubzick, C, D'Angelo, J, Randolph, G, Shay, T, Regev, A, Gazit, R, Rossi, D, Kreslawsky, T, von Bohmer, H, Bellemare-Pelletier, A, Elpek, K, Spelv, L, Fletcher, A, Malhotra, D, Cremasco, V, Turley, S, Kim, F, Nageswara Rao, T, and Wagers, A

Subjects
Immunology
Published
2014

5. Stable Oxide Nanoparticle Clusters Obtained by Complexation

Author

Berret, J. -F., Sehgal, A., Morvan, M., Sandre, O., Vacher, A., and Airiau, M.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We report on the electrostatic complexation between polyelectrolyte-neutral copolymers and oppositely charged 6 nm-crystalline nanoparticles. For two different dispersions of oxide nanoparticles, the electrostatic complexation gives rise to the formation of stable nanoparticle clusters in the range 20 - 100 nm. It is found that inside the clusters, the particles are pasted together by the polyelectrolyte blocks adsorbed on their surface. Cryo-transmission electronic microscopy allows to visualize the clusters and to determine the probability distributions functions in size and in aggregation number. The comparison between light scattering and cryo-microscopy results suggests the existence of a polymer brush around the clusters., Comment: 7 pages, 4 figures, to appear in JCIS

Published
2006
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6. Precipitation-Redispersion of Cerium Oxide Nanoparticles with Poly(Acrylic Acid) : Towards Stable Dispersions

Author

Sehgal, A., Lalatonne, Y., Berret, J. -F., and Morvan, M.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We exploit a precipitation-redispersion mechanism for complexation of short chain polyelectrolytes with cerium oxide nanoparticles to extend their stability ranges. As synthesized, cerium oxide sols at pH 1.4 consist of monodisperse cationic nanocrystalline particles having a hydrodynamic diameter of 10 nm and a molecular weight 400000 gmol-1. We show that short chain uncharged poly(acrylic acid) at low pH when added to a cerium oxide sols leads to macroscopic precipitation. As the pH is increased, the solution spontaneously redisperses into a clear solution of single particles with an anionic poly(acrylic acid) corona. The structure and dynamics of cerium oxide nanosols and their hybrid polymer-inorganic complexes in solution are investigated by static and dynamic light scattering, X-ray scattering, and by chemical analysis. Quantitative analysis of the redispersed sol gives rise to an estimate of 40 - 50 polymer chains per particle for stable suspension. This amount represents 20 % of the mass of the polymer-nanoparticle complexes. This complexation adds utility to the otherwise unstable cerium oxide dispersions by extending the range of stability of the sols in terms of pH, ionic strength and concentration., Comment: 6 Figures, 23 pages, submitted

Published
2005
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7. Electrostatic Self-assembly : A New Route Towards Nanostructures

Author

Berret, J. -F., Herve, P., Morvan, M., Yokota, K., Destarac, M., Oberdisse, J., Grillo, I., and Schweins, R.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

During the last 3 years, our group has investigated extensively the complexation mechanism between neutral-polyelectrolyte block copolymers with oppositely charged species. These species are surfactant micelles, multivalent counterions and inorganic nanoparticles. In the three cases, we have established the thermodynamical phase diagram of these systems, and found broad regions where supramolecular aggregates spontaneously form via electrostatic self-assembly. From earlier works, it was suspected that these mixed colloids exhibit a core-shell structure. However, their inner structure was unveiled by us only recently, using a combination of light, neutron and x-ray scattering experiments., Comment: 5 pages, 4 figures, to appear in Institute Laue-Langevin Soft Matter Brochure

Published
2005

8. Interactions between Polymers and Nanoparticles : Formation of Supermicellar Hybrid Aggregates

Author

Berret, J. -F., Yokota, K., and Morvan, M.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

When polyelectrolyte-neutral block copolymers are mixed in solutions to oppositely charged species (e.g. surfactant micelles, macromolecules, proteins etc), there is the formation of stable supermicellar aggregates combining both components. The resulting colloidal complexes exhibit a core-shell structure and the mechanism yielding to their formation is electrostatic self-assembly. In this contribution, we report on the structural properties of supermicellar aggregates made from yttrium-based inorganic nanoparticles (radius 2 nm) and polyelectrolyte-neutral block copolymers in aqueous solutions. The yttrium hydroxyacetate particles were chosen as a model system for inorganic colloids, and also for their use in industrial applications as precursors for ceramic and opto-electronic materials. The copolymers placed under scrutiny are the water soluble and asymmetric poly(sodium acrylate)poly(acrylamide) diblocks. Using static and dynamical light scattering experiments, we demonstrate the analogy between surfactant micelles and nanoparticles in the complexation phenomenon with oppositely charged polymers. We also determine the sizes and the aggregation numbers of the hybrid organic-inorganic complexes. Several additional properties are discussed, such as the remarkable stability of the hybrid aggregates and the dependence of their sizes on the mixing conditions., Comment: 26 pages, 7 figures, 1 table

Published
2004
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9. Stabilization and Controlled Association of Inorganic Nanoparticles using Block Copolymers

Author

Yokota, K., Morvan, M., Berret, J. -F., and Oberdisse, J.

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We report on the structural properties of mixed aggregates made from rare-earth inorganic nanoparticles (radius 20 Angstroms) and polyelectrolyte-neutral block copolymers in aqueous solutions. Using scattering experiments and Monte Carlo simulations, we show that these mixed aggregates have a hierarchical core-shell microstructure. The core is made of densely packed nanoparticles and it is surrounded by a corona of neutral chains. This microstructure results from a process of controlled association and confers to the hybrid aggregates a remarkable colloidal stability., Comment: 14 pages, 5 figures

Published
2004
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10. Quelles mesures pour maîtriser le risque infectieux chez les patients immunodéprimés ? Recommandations formalisées d’experts

Author

Zahar, J.-R., Jolivet, S., Adam, H., Dananché, C., Lizon, J., Alfandari, S., Boulestreau, H., Baghdadi, N., Bay, J.-O., Bénéteau, A.-M., Bougnoux, M.-E., Brenier-Pinchart, M.-P., Dalle, J.-H., Fournier, S., Fuzibet, J.-G., Kauffmann-Lacroix, C., Le Guinche, I., Lepelletier, D., Loukili, N., Lory, A., Morvan, M., Oumedaly, R., Ribaud, P., Rohrlich, P., Vanhems, P., Aho, S., Vanjak, D., and Gangneux, J.-P.

Published
2017
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11. Structure of some sand pile model

Author

Latapy, M., Mantaci, R., Morvan, M., and Phan, H. D.

Subjects
Computer Science - Discrete Mathematics, Condensed Matter - Statistical Mechanics, Computer Science - Data Structures and Algorithms, Mathematics - Combinatorics, G.2.1, J.2
Abstract

SPM (Sand Pile Model) is a simple discrete dynamical system used in physics to represent granular objects. It is deeply related to integer partitions, and many other combinatorics problems, such as tilings or rewriting systems. The evolution of the system started with n stacked grains generates a lattice, denoted by SPM(n). We study here the structure of this lattice. We first explain how it can be constructed, by showing its strong self-similarity property. Then, we define SPM(infini), a natural extension of SPM when one starts with an infinite number of grains. Again, we give an efficient construction algorithm and a coding of this lattice using a self-similar tree. The two approaches give different recursive formulae for the cardinal of SPM(n), where no closed formula have ever been found., Comment: To appear in Theoretical Computer Science

Published
2000

13. ExoClock Project. III. 450 New Exoplanet Ephemerides from Ground and Space Observations

Author

Kokori, A., primary, Tsiaras, A., additional, Edwards, B., additional, Jones, A., additional, Pantelidou, G., additional, Tinetti, G., additional, Bewersdorff, L., additional, Iliadou, A., additional, Jongen, Y., additional, Lekkas, G., additional, Nastasi, A., additional, Poultourtzidis, E., additional, Sidiropoulos, C., additional, Walter, F., additional, Wünsche, A., additional, Abraham, R., additional, Agnihotri, V. K., additional, Albanesi, R., additional, Arce-Mansego, E., additional, Arnot, D., additional, Audejean, M., additional, Aumasson, C., additional, Bachschmidt, M., additional, Baj, G., additional, Barroy, P. R., additional, Belinski, A. A., additional, Bennett, D., additional, Benni, P., additional, Bernacki, K., additional, Betti, L., additional, Biagini, A., additional, Bosch, P., additional, Brandebourg, P., additional, Brát, L., additional, Bretton, M., additional, Brincat, S. M., additional, Brouillard, S., additional, Bruzas, A., additional, Bruzzone, A., additional, Buckland, R. A., additional, Caló, M., additional, Campos, F., additional, Carreño, A., additional, Carrion Rodrigo, J. A., additional, Casali, R., additional, Casalnuovo, G., additional, Cataneo, M., additional, Chang, C.-M., additional, Changeat, L., additional, Chowdhury, V., additional, Ciantini, R., additional, Cilluffo, M., additional, Coliac, J.-F., additional, Conzo, G., additional, Correa, M., additional, Coulon, G., additional, Crouzet, N., additional, Crow, M. V., additional, Curtis, I. A., additional, Daniel, D., additional, Dauchet, B., additional, Dawes, S., additional, Deldem, M., additional, Deligeorgopoulos, D., additional, Dransfield, G., additional, Dymock, R., additional, Eenmäe, T., additional, Esseiva, N., additional, Evans, P., additional, Falco, C., additional, Farfán, R. G., additional, Fernández-Lajús, E., additional, Ferratfiat, S., additional, Ferreira, S. L., additional, Ferretti, A., additional, Fiołka, J., additional, Fowler, M., additional, Futcher, S. R., additional, Gabellini, D., additional, Gainey, T., additional, Gaitan, J., additional, Gajdoš, P., additional, García-Sánchez, A., additional, Garlitz, J., additional, Gillier, C., additional, Gison, C., additional, Gonzales, J., additional, Gorshanov, D., additional, Grau Horta, F., additional, Grivas, G., additional, Guerra, P., additional, Guillot, T., additional, Haswell, C. A., additional, Haymes, T., additional, Hentunen, V.-P., additional, Hills, K., additional, Hose, K., additional, Humbert, T., additional, Hurter, F., additional, Hynek, T., additional, Irzyk, M., additional, Jacobsen, J., additional, Jannetta, A. L., additional, Johnson, K., additional, Jóźwik-Wabik, P., additional, Kaeouach, A. E., additional, Kang, W., additional, Kiiskinen, H., additional, Kim, T., additional, Kivila, Ü., additional, Koch, B., additional, Kolb, U., additional, Kučáková, H., additional, Lai, S.-P., additional, Laloum, D., additional, Lasota, S., additional, Lewis, L. A., additional, Liakos, G.-I., additional, Libotte, F., additional, Lomoz, F., additional, Lopresti, C., additional, Majewski, R., additional, Malcher, A., additional, Mallonn, M., additional, Mannucci, M., additional, Marchini, A., additional, Mari, J.-M., additional, Marino, A., additional, Marino, G., additional, Mario, J.-C., additional, Marquette, J.-B., additional, Martínez-Bravo, F. A., additional, Mašek, M., additional, Matassa, P., additional, Michel, P., additional, Michelet, J., additional, Miller, M., additional, Miny, E., additional, Molina, D., additional, Mollier, T., additional, Monteleone, B., additional, Montigiani, N., additional, Morales-Aimar, M., additional, Mortari, F., additional, Morvan, M., additional, Mugnai, L. V., additional, Murawski, G., additional, Naponiello, L., additional, Naudin, J.-L., additional, Naves, R., additional, Néel, D., additional, Neito, R., additional, Neveu, S., additional, Noschese, A., additional, Öğmen, Y., additional, Ohshima, O., additional, Orbanic, Z., additional, Pace, E. P., additional, Pantacchini, C., additional, Paschalis, N. I., additional, Pereira, C., additional, Peretto, I., additional, Perroud, V., additional, Phillips, M., additional, Pintr, P., additional, Pioppa, J.-B., additional, Plazas, J., additional, Poelarends, A. J., additional, Popowicz, A., additional, Purcell, J., additional, Quinn, N., additional, Raetz, M., additional, Rees, D., additional, Regembal, F., additional, Rocchetto, M., additional, Rocci, P.-F., additional, Rockenbauer, M., additional, Roth, R., additional, Rousselot, L., additional, Rubia, X., additional, Ruocco, N., additional, Russo, E., additional, Salisbury, M., additional, Salvaggio, F., additional, Santos, A., additional, Savage, J., additional, Scaggiante, F., additional, Sedita, D., additional, Shadick, S., additional, Silva, A. F., additional, Sioulas, N., additional, Školník, V., additional, Smith, M., additional, Smolka, M., additional, Solmaz, A., additional, Stanbury, N., additional, Stouraitis, D., additional, Tan, T.-G., additional, Theusner, M., additional, Thurston, G., additional, Tifner, F. P., additional, Tomacelli, A., additional, Tomatis, A., additional, Trnka, J., additional, Tylšar, M., additional, Valeau, P., additional, Vignes, J.-P., additional, Villa, A., additional, Sureda, A. Vives, additional, Vora, K., additional, Vrašt’ák, M., additional, Walliang, D., additional, Wenzel, B., additional, Wright, D. E., additional, Zambelli, R., additional, Zhang, M., additional, and Zíbar, M., additional

Published
2023
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17. Modeling Chemical EOR Processes: Some Illustrations from Lab to Reservoir Scale Modélisation des procédés EOR chimiques : du laboratoire au réservoir

Author

Douarche F., Rousseau D., Bazin B., Tabary R., Moreau P., and Morvan M.

Subjects
Chemical technology, TP1-1185, Energy industries. Energy policy. Fuel trade, HD9502-9502.5
Abstract

Chemical flooding, SP (Surfactant Polymer) or ASP (Alkali-Surfactant-Polymer), are of increasing interest due to the need to increase oil production. Design of chemical processes is very project specific and requires case by case studies including various steps among which reservoir data analysis, chemical formulations, coreflood validations and reservoir simulation. Every step is dependent on the preceding ones and the last reservoir simulation step gathers all the information collected during the project. In this paper, we present a chemical simulator describing two phase flow with chemical transport of alkali, surfactant, polymer and salinity. Two phase flow is related to capillary desaturation curve through the decrease of oil-water interfacial tension. Physical chemistry reactions are described either with a thermodynamic approach or a simplified one using tables or simplified physics to be compatible with large scale reservoir simulations. In this paper, we describe the simulator and present results of numerous experiments specially designed to validate the model: alkaline injections of carbonates and borates, surfactant adsorption experiments at different salinities and pH, systematic effect of salinity on interfacial tension and oil recovery with/without salinity gradient. The good agreement between the experimental and numerical oil recoveries and chemical compositions is very encouraging and supports the validity of the physics implemented in the simulator. In particular, the dominant effect of pH on adsorption and the importance of a salinity gradient on oil recovery is highlighted by numerical simulation. Finally, a sensitivity study at the reservoir scale is presented to illustrate relevant factors for the implementation of an economic surfactant-based process. Les procédés de récupération tertiaire par voie chimique, SP (Surfactant Polymer) ou ASP (Alkali-Surfactant-Polymer), sont en plein essor du fait d’une demande croissante en produits pétroliers. La mise en œuvre des méthodes de récupération d’huile par voie chimique sont très spécifiques et demandent des études intégrées allant de l’étude du réservoir à la simulation du procédé à l’échelle du réservoir, sans oublier les études de laboratoire. Cet article présente le simulateur chimique SARIPCH développé pour les évaluations à l’échelle du réservoir. Il s’agit d’un simulateur de type ‘‘black oil’’ incorporant des équations de transport pour les produits chimiques : alcalin, tensio-actif et polymère. Le processus de récupération d’huile est introduit par la courbe de désaturation capillaire. Les réactions physico-chimiques sont décrites en utilisant soit une approche thermodynamique, complète ou simplifiée, soit des tables de façon à rendre les calculs plus efficaces. Dans cet article, on décrit le simulateur et on présente des résultats expérimentaux destinés à valider la physique du simulateur : injection alcaline avec carbonates ou métaborates comme additif alcalin, expériences d’adsorption en fonction de la salinité et du pH, effet systématique de la salinité sur la tension interfaciale et expériences de récupération d’huile avec ou sans gradient de salinité. La bonne adéquation entre résultats expérimentaux et résultats calculés par le simulateur, que ce soit sur les courbes d’élution des produits chimiques ou sur les taux de récupération d’huile, est encourageante et prouve la validité de la physique introduite dans le simulateur. Des études de sensibilité montrent l’impact majeur de la courbe de désaturation capillaire et de l’adsorption sur les taux de récupération d’huile. Pour finir, une approche économique, fondée sur des simulations numériques, fournit des guides à l’échelle du réservoir.

Published
2013
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18. Axisymmetric Drainage in Hydrophobic Porous Media Micromodels Drainage en géométrie axisymétrique dans des milieux poreux hydrophobes à deux dimensions

Author

Cuenca A., Chabert M., Morvan M., and Bodiguel H.

Subjects
Chemical technology, TP1-1185, Energy industries. Energy policy. Fuel trade, HD9502-9502.5
Abstract

We present studies of axisymmetric drainage in two-dimensional micromodels of porous media using up to date microfabrication and image analysis methods. Drainage of model oil by aqueous solutions is studied at low capillary numbers (Ca) typically encountered during oil recovery operations. We use two types of oil-wet micromodels: one is based on a deposition method for creating a random monolayer of micronic glass beads, while the other is made using computer generated random networks etched in glass using wet-lithography. Both models have a central injection scheme and a radial geometry, resulting in a continuous variation of the capillary number during the course of drainage. We first carry out an analysis of experiments at global micromodel scale using computer based image analysis coupled with flow rates and pressure drop measurements. Basic relevant parameters such as permeability, porosity of the micromodel and residual oil in place after waterflooding are extracted. We then take advantage of the ease of observation in transparent micromodels to investigate the drainage phenomenon at local scale. Local saturation and front width are measured as a function of the local capillary number. Interestingly, because of the radial flow geometry, our experiments allow a continuous plotting of the micromodels capillary desaturation curve on several decades. As expected but never precisely observed, all points of various experiments collapse on a single capillary desaturation curve for a given micromodel. However, we observe dissimilar behaviors between the two types of micromodels. We discuss this phenomenon in light of the pore scale geometrical differences between the two models. Nous présentons une étude de phénomènes de drainage dans des micromodèles bidimensionnels de milieu poreux s’appuyant sur des méthodes modernes de microfabrication et d’analyse. Le drainage d’huile par des solutions aqueuses est étudié à de faibles nombres capillaires (Ca) communément rencontrés lors des opérations d’extraction pétrolière. Nous utilisons deux types de micromodèles mouillables à l’huile : le premier est basé sur une méthode de déposition innovante permettant d’obtenir des monocouches de billes de verre de taille micronique, tandis que le second est microfabriqué dans du verre à partir de réseaux poreux aléatoires générés informatiquement. Chacun des modèles utilise un schéma d’injection central dans une géométrie radiale, ce qui engendre une variation continue du nombre capillaire pendant le drainage. Nous menons tout d’abord une analyse du drainage à l’échelle globale du micromodèle en couplant analyse d’image et mesures de pression et de débit. Les paramètres de base tels que perméabilité, porosité et saturation résiduelle en huile des modèles sont extraits dans cette première phase. Nous exploitons ensuite les possibilités de visualisation offertes par les micromodèles transparents pour mener une analyse locale du phénomène d’invasion. Les saturations locales et la largeur de front sont mesurées en fonction du nombre capillaire local. De façon intéressante, du fait de la géométrie radiale, nos expériences permettent de tracer continûment les courbes de désaturation capillaire sur plusieurs décades. Comme inféré, mais jamais observé précisément, les mesures de diverses expériences se regroupent sur une courbe maîtresse pour un micromodèle donné. Nous observons cependant des différences notables entre les deux types de micromodèle. Ces observations sont discutées à la lumière des différences géométriques existant entre les deux micromodèles à l’échelle du pore.

Published
2013
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20. ExoClock Project. II. A Large-scale Integrated Study with 180 Updated Exoplanet Ephemerides

Author

Kokori, A., primary, Tsiaras, A., additional, Edwards, B., additional, Rocchetto, M., additional, Tinetti, G., additional, Bewersdorff, L., additional, Jongen, Y., additional, Lekkas, G., additional, Pantelidou, G., additional, Poultourtzidis, E., additional, Wünsche, A., additional, Aggelis, C., additional, Agnihotri, V. K., additional, Arena, C., additional, Bachschmidt, M., additional, Bennett, D., additional, Benni, P., additional, Bernacki, K., additional, Besson, E., additional, Betti, L., additional, Biagini, A., additional, Brandebourg, P., additional, Bretton, M., additional, Brincat, S. M., additional, Caló, M., additional, Campos, F., additional, Casali, R., additional, Ciantini, R., additional, Crow, M. V., additional, Dauchet, B., additional, Dawes, S., additional, Deldem, M., additional, Deligeorgopoulos, D., additional, Dymock, R., additional, Eenmäe, T., additional, Evans, P., additional, Esseiva, N., additional, Falco, C., additional, Ferratfiat, S., additional, Fowler, M., additional, Futcher, S. R., additional, Gaitan, J., additional, Horta, F. Grau, additional, Guerra, P., additional, Hurter, F., additional, Jones, A., additional, Kang, W., additional, Kiiskinen, H., additional, Kim, T., additional, Laloum, D., additional, Lee, R., additional, Lomoz, F., additional, Lopresti, C., additional, Mallonn, M., additional, Mannucci, M., additional, Marino, A., additional, Mario, J.-C., additional, Marquette, J.-B., additional, Michelet, J., additional, Miller, M., additional, Mollier, T., additional, Molina, D., additional, Montigiani, N., additional, Mortari, F., additional, Morvan, M., additional, Mugnai, L. V., additional, Naponiello, L., additional, Nastasi, A., additional, Neito, R., additional, Pace, E., additional, Papadeas, P., additional, Paschalis, N., additional, Pereira, C., additional, Perroud, V., additional, Phillips, M., additional, Pintr, P., additional, Pioppa, J.-B., additional, Popowicz, A., additional, Raetz, M., additional, Regembal, F., additional, Rickard, K., additional, Roberts, M., additional, Rousselot, L., additional, Rubia, X., additional, Savage, J., additional, Sedita, D., additional, Shave-Wall, D., additional, Sioulas, N., additional, Školník, V., additional, Smith, M., additional, St-Gelais, D., additional, Stouraitis, D., additional, Strikis, I., additional, Thurston, G., additional, Tomacelli, A., additional, Tomatis, A., additional, Trevan, B., additional, Valeau, P., additional, Vignes, J.-P., additional, Vora, K., additional, Vrašťák, M., additional, Walter, F., additional, Wenzel, B., additional, Wright, D. E., additional, and Zíbar, M., additional

Published
2022
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23. Remarks on some concurrency measures

Author

Habib, M., Morvan, M., Rampon, J. X., Goos, G., editor, Hartmanis, J., editor, Barstow, D., editor, Brauer, W., editor, Brinch Hansen, P., editor, Gries, D., editor, Luckham, D., editor, Moler, C., editor, Pnueli, A., editor, Seegmüller, G., editor, Stoer, J., editor, Wirth, N., editor, and Möhring, Rolf H., editor

Published
1991
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28. Incorporating porosity-dependent hysteretic water retention behavior into a new constitutive model of unsaturated soils

Author

Morvan, M., Wong, H., and Branque, D.

Subjects
Hysteresis -- Research, Soil moisture -- Research, Porosity -- Research, Soil permeability -- Research, Earth sciences
Abstract

A new unsaturated soil model was recently developed at Ecole Nationale des Travaux Publics de l'Etat (ENTPE), based on the concept of bounding surface plasticity. The first version of this model (by Morvan et al. in 2010) only required 12 parameters for its definition, and yet can simulate a few behaviors typically observed on unsaturated fine sands, which more classical models fail to reproduce. These include post-peak softening, change from contractant to dilatant behavior during shearing, and the smooth transition from elastic to elastoplastic behavior upon yielding. Subsequent to this first publication, additional mechanisms have been introduced in the model previously developed. Among them, the hysteretic phenomenon during cyclic variations of suction and water content, as well as the effects of porosity change on water retention characteristics, are now taken into consideration. To this end, the water content is introduced as an independent generalized strain variable, which is no longer uniquely linked to suction. Thanks to these developments, the model can now account for the bilateral couplings between hydraulic and mechanical quantities, with good precision under very general loading conditions. In the present paper, these new developments are presented in detail, and the experimental basis of this construction is discussed. The model is then validated using existing experimental data on kaolin, by considering two stress paths. The first stress path consists of a single cycle of wetting followed by drying at constant isotropic stress. The second, more complex loading path involves simultaneous variations of suction and isotropic compression or decompression. The results confirm overall the satisfactory performance of the model. The main conclusions are then summarized in the last section, including perspectives for future developments. Key words: bounding surface plasticity, suction hardening, critical state line, limit state line, experimental validation, hydraulic hysteresis, hydromechanical coupling. Un nouveau modele de sol non sature a ete developpe recemment a Ecole Nationale des Travaux Publics de l'Etat (l'ENTPE), selon le concept de la surface limite de plasticite. La premiere version de ce modele (par Morvan et al. en 2010) necessitait seulement 12 parametres pour sa definition, mais pouvait tout de meme simuler quelques comportements typiques observes sur des sables non satures dont les modeles plus classiques n'arrivaient pas a reproduire. Ceux-ci incluent l'adoucissement post-pic, le changement d'un comportement contractant a un comportement dilatant durant le cisaillement, et la transition graduelle d'un comportement elastique a elasto-plastique a la limite elastique. Suite a cette premiere publication, des mecanismes additionnels ont ete introduits au modele developpe precedemment. Parmi ces mecanismes, le phenomene d' hysteresis durant les variations cycliques de la succion et de la teneur en eau, et les effets de la variation de la porosite sur les caracteristiques de retention d'eau, sont maintenant consideres. Ainsi, la teneur en eau est introduite en tant que variable independante generalisee de la deformation qui n'est plus seulement liee a la succion. Grace a ces developpements, le modele peut maintenant considerer les couplages bilateraux entre les quantites hydrauliques et mecaniques avec une bonne precision sous des conditions de chargement tres generales. Dans cet article, ces nouveaux developpements sont presentes en details, et la base experimentale de l'elaboration est discutee. Le modele est ensuite valide a l'aide de donnees experimentales sur le kaolin en considerant deux cheminements des contraintes. Le premier cheminement des contraintes consiste en un seul cycle de mouillage suivi par le sechage a une contrainte isotrope constante. Le deuxieme et plus complexe cheminement des contraintes implique des variations simultanees de la succion et de la compression ou decompression isotrope. Les resultats confirment la performance globalement satisfaisante du modele. Les principales conclusions sont ensuite resumees dans la derniere section, incluant des perspectives pour le developpement futur. Mots-cles : surface limite de plasticite, durcissement par succion, ligne de l'etat critique, ligne de l'etat limite, validation experimentale, hysteresis hydraulique, couplage hydromecanique. [Traduit par la Redaction], Introduction During the last 20 years, a certain number of theoretical models were built to simulate the behavior of unsaturated soils. The Barcelona basic model (BBM) developed by Alonso et [...]

Published
2011
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34. The dialogue between mast cells and B cells worsens the pathology of abdominal aortic aneurysms

Author

Loste, A., primary, Clement, M., additional, Delbosc, S., additional, Guedj, K., additional, Procopio, E., additional, Gaston, A.T., additional, Morvan, M., additional, Even, G., additional, Deschildre, C., additional, Michel, J.B., additional, Gautier, G., additional, Launey, P., additional, Eggel, A., additional, Arock, M., additional, Deschamps, L., additional, Caligiuri, G., additional, Nicoletti, A., additional, and Le Borgne, M., additional

Published
2019
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35. Blood penetration into human aortic valves consecutive to endothelial micro-fissuring of the fibrosa determines the site of calcium deposition: Physiopathological implications

Author

Arangalage, D., primary, Morvan, M., additional, Perez, F., additional, Cattan-Levy, L., additional, Messika-Zeitoun, D., additional, Codogno, I., additional, Jacob-Lenet, M.P., additional, Deschildre, C., additional, Choqueux, C., additional, Even, G., additional, Michel, J.B., additional, Bäck, M., additional, Nicoletti, A., additional, Caligiuri, G., additional, and Laschet, J., additional

Published
2019
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39. Direct contact with intra-tissue senescent erythrocytes accumulated following endothelial injury triggers the acquisition of an osteoblastic phenotype by aortic valve interstitial cells

Author

Arangalage, D., primary, Morvan, M., additional, Perez, F., additional, Cattan-Levy, L., additional, Messika-Zeitoun, D., additional, Codogno, I., additional, Deschildre, C., additional, Choqueux, C., additional, Back, M., additional, Deschamps, L., additional, Michel, J.B., additional, Nicoletti, A., additional, Caligiuri, G., additional, and Laschet, J., additional

Published
2018
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44. Niches environnementales et circuit de transmission des bactéries hydriques dans un service hospitalier à réseau d’eau protégé

Author

Hicheri, Yosr, Mercier, L., Morvan, M., Lotthe, L., Baranovsky, Sophie, Romano-Bertrand, Sara, Jumas-Bilak, Estelle, roussel, pascale, Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Pathogènes Hydriques Santé Environnement (PHySE ), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio]
Abstract

International audience; Pseudomonas aeruginosa est une bactérie hydrique en causedans les infections et les épidémies associées aux soins.Le génotype ST308 colonise le réseau d’eau d’un serviced’oncologie-hématologie. Les points d’eau utilisés pour lessoins ont été équipés de filtres antimicrobiens mais un patienta déclaré une bactériémie à P. aeruginosa ST308, ce quisuggère un défaut de filtration ou une circulation secondairedes pathogènes hydriques.L’objectif est d’évaluer l’efficacité de la filtration antimicrobienneterminale et les circuits secondaires de circulation et detransmission de bactéries hydriques dans un service à réseaud’eau protégé.

Published
2016

46. Plasma from patients with calcified aortic disease triggers an osteoblast-like phenotype switch in human aortic valve interstitial cells

Author

Cattan Levy, L., primary, Jacob-Lenet, M.P., additional, Dehoux, M.P., additional, Deschildre, C., additional, Codogno, I., additional, Morvan, M., additional, Gaston, A.T., additional, Even, G., additional, Michel, J., additional, Messika-Zeitoun, D., additional, Nicoletti, A., additional, Caligiuri, G., additional, and Laschet, J., additional

Published
2017
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47. Transmission persistante de Klebsiella pneumoniae productrice de carbapénémase rapportée à un réservoir environnemental

Author

Clarivet, Béatrice, Grau, Delphine, Pantel, A., Jean-Pierre, H, Morvan, M., Jumas-Bilak, Estelle, Lotthé, Anne, Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and roussel, pascale

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

50. Plasma from patients with calcified aortic disease triggers an osteoblast-like phenotype switch in human aortic valve interstitial cells

Author

Cattan-Lévy, L., primary, Jacob-Lenet, M.P., additional, Dehoux, M., additional, Deschildre, C., additional, Codogno, I., additional, Morvan, M., additional, Gaston, A.T., additional, Even, G., additional, Michel, J.B., additional, Messika-Zeitoun, D., additional, Nicoletti, A., additional, Caligiuri, G., additional, and Khallou-Laschet, J., additional

Published
2016
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