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Arnal Audrey, Vittecoq Marion, Pearce-Duvet Jessica, Gauthier-Clerc Michel, Boulinier Thierry, Jourdain Elsa, . (2014). Laridae: A neglected reservoir that could play a major role in avian influenza virus epidemiological dynamics
. Critical Reviews in Microbiology, , 1–12.
Abstract: Avian influenza viruses (AIVs) are of great concern worldwide due to their economic impact and the threat they represent to human health. As wild birds are the natural reservoirs of AIVs, understanding AIV dynamics in different avian taxa is essential for deciphering the epidemiological links between wildlife, poultry and humans. To date, only the Anatidae (ducks, geese and swans) have been widely studied. Here, we aim to shed light on the current state of knowledge on AIVs in Laridae (gulls, terns and kittiwakes) versus that in Anatidae by setting forth four fundamental questions: how, when, where and to which host species are AIVs transmitted? First, we describe ecological differences between Laridae and Anatidae and discuss how they may explain observed contrasts in preferential transmission routes and the evolution of specific AIV subtypes. Second, we highlight the dissimilarities in the temporal patterns of AIV shedding between Laridae and Anatidae and address the role that immunity likely plays in shaping these patterns. Third, we underscore that Laridae may be key in promoting intercontinental exchanges of AIVs. Finally, we emphasize the crucial epidemiological position that Laridae occupy between wildlife, domestic birds and humans.
Programme: 333
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Fourati H, Manamanni N, Afilal L, Handrich Y, . (2009). A rigid body attitude estimation for Bio-logging application: A quaternion-based nonlinear filter approach
. Bachelor's thesis, IEEE, .
Abstract: Bio-logging is a new interdisciplinary research area at the intersection of animal behavior and bioengineering. It involves several applications such as determination of specific parameters (attitude, acceleration, and position) via a new generation of mechatronic systems. The aim of this paper concerns the animal motion estimation problem using low-cost sensors fusion. A quaternion-based nonlinear observer for the tracking of rigid body attitude (orientation) and heading using measurements provided from low cost inertial and magnetic sensors is presented. The algorithm combines low-frequency, 3-axis accelerometer and 3-axis magnetometer, data with high frequency 3-axis gyroscope measurement. Then, to increase the performance and reduce the computational requirements, we exploit the sensor readings directly in the designed observer. Using the estimated attitude, the linear acceleration is then derived. This latter will be used in the future to evaluate the animal energy index and its mechanical work. Finally, some experimental results, using the measurements provided by an inertial sensor put on dog are given to illustrate the efficiency of the proposed algorithm.
Programme: 394
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Geoffroy, L.; Aubourg, C.; Callot, J.-P.; Barrat, J.-A. (2007). Mechanisms of crustal growth in large igneous provinces: The north Atlantic province as a case study. Geological Society of America Special Papers, 430, 747–774.
Abstract: The mechanisms of magma crust accretion at large igneous provinces (LIPs) are questioned using arguments based on the north Atlantic case. Published and new data on the calculated flow vectors within dike swarms feeding the early traps and subsequent seaward-dipping reflector lavas suggest that most of the mafic magmas forming the north Atlantic LIP transited through a small number of igneous centers. The magma was injected centrifugally in dike swarms at some distance away from individual igneous centers along the trend of the maximum horizontal stress acting in the crust, feeding lava piles via dikes intersecting the ground surface. This mechanism is similar to that observed in present-day Iceland and, more generally, in mafic volcano-tectonic systems. The absence of generalized vertical magma transit in a LIP has major geodynamic consequences. We cannot link the surface extent of LIP magmas to the dimensions of the mantle melting zone as proposed in former plume head models. The distribution of LIP magmas at the surface is primarily controlled by the regional stress field acting within the upper crust, but is also affected by magma viscosity. The igneous centers feeding LIPs most likely represent the crustal expression of small-scale convective cells of the buoyant mantle naturally located beneath the mechanical lithosphere.
Keywords: traps; volcanic margin; dike swarm; small-scale convection; AMS
Programme: 290
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O'Toole Malcolm D, Lea Mary-Anne, Guinet Christophe, Schick Robert, Hindell Mark A, . (2015). Foraging strategy switch of a top marine predator according to seasonal resource differences
. Frontiers in Marine Science, 2, 21.
Abstract: The spatio-temporal variability in marine resources influences the foraging behaviour and success of top marine predators. However, little is known about the links between these animals and ocean productivity, specifically, how plankton density influences their foraging behaviour. Southern elephant seals (Mirounga leonina) have two annual at-sea foraging trips: a two month post-breeding foraging trip (Nov – Jan) that coincides with elevated summer productivity; and an eight month post-moulting foraging trip (Feb – Oct) over winter, when productivity is low. Physical parameters are often used to describe seal habitat, whereas information about important biological parameters is lacking. We used electronic tags deployed on elephant seals during both trips to determine their movement and foraging behaviour. The tags also recorded light, which measured the bio-optical properties of the water column, the bulk of which is presumably influenced by phytoplankton. We investigated the relationship between plankton density and seal foraging behaviour; comparing trends between summer and winter trips. We found a positive relationship between plankton density and foraging behaviour, which did not vary seasonally. We propose that profitable concentrations of seal prey are more likely to coincide with planktonic aggregations, but we also acknowledge that trophic dynamics may shift in response to seasonal trends in productivity. Seal prey (mid-trophic level) and plankton (lower-trophic level) are expected to overlap in space and time during summer trips when peak phytoplankton blooms occur. In contrast, aggregated patches of lower trophic levels are likely to be more dispersed during winter trips when plankton density is considerably lower and heterogeneous. These results show that southern elephant seals are able to exploit prey resources in different ways throughout the year as demonstrated by the variation observed between seal foraging behaviour and trophic dynamics.
Keywords: Antarctica, Mirounga leonina, Ross Sea, Trophic link, elephant seal, foraging behavior, lower-trophic distribution,
Programme: 109
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Maj Émilie, . (2010). Le néo-eurasisme : relecture du passé et construction du futur. Didier Chaudet, Florent Parmentier et Benoît Pélopidas, LEmpire au miroir. Stratégies de puissance aux États-Unis et en Russie , 2007.
. EspacesTemps.net.
Abstract: Didier Chaudet, Florent Parmentier et Benoît Pélopidas, tous trois doctorants en science politique rattachés au Centre détudes et de recherches internationales ( Ceri ), nous proposent un ouvrage consacré au renouveau de lidée dempire en Russie et aux États-Unis en ce début de 21 e siècle et, plus particulièrement, après léclatement de lUnion soviétique. Lanalyse se fait sur le mode binaire, chaque partie comportant un commentaire portant dabord sur lAmérique puis sur la Russie. Preuve de la complexité et de la richesse de lanalyse, lindex reprend les noms de 214 personnalités issues de courants spirituels ou politiques cités dans le corps du texte. À travers une analyse historique, cette étude de politique comparée sintéresse à « des conceptions globalisantes, des visions du monde » (p. 13) et, précisément, à deux mouvements, celui des néoconservateurs aux États-Unis et des néo-eurasistes en Russie. En marge de lanalyse, vingt-deux encadrés renseignent le lecteur sur des mouvements politiques parallèles, des courants spirituels, des guerres ou des révolutions. Le livre est construit en trois parties, une première historique, une seconde consacrée aux idées dempire et de nationalisme et une troisième qui sinterroge sur le rapport de ces deux pays à lislam. Lintention des auteurs est de mettre en parallèle les politiques menées aux États-Unis et en Russie au 20 e siècle.
Programme: 1024
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Provencher Jf, Borrelle Sb, Sherley Rb, Avery-gomm S, Hodum P, Bond A, Major Hl, Mccoy Kd, Crawford R, Merkel F, Votier S, Reynolds M, Hatfield J, Spatz D, Mallory Ml. 2019. (2018). Seabirds (Charles Sheppard, Ed.). Bachelor's thesis, Esevier, inc., .
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Fort Jérôme, Porter Warren P, Grémillet David, . (2011). Energetic modelling: a comparison of the different approaches used in seabirds.
. Comp. Biochem. Physiol., Part A Mol. Integr. Physiol., 158(3), 358–365.
Abstract: Studying energetics of marine top predators is essential to understand their role within food-webs and mechanisms associated with their survival and population dynamics. Several methods exist to estimate energy expenditure in captive and free-ranging animals. However, most of them are difficult to implement, restrained to specific periods, and are consequently inappropriate for seabirds. Supplementary and complementary approaches are therefore needed, and the use of modelling appears as an excellent option allowing energetic studies when field data collection is challenging. Currently three main energetics models are used, with various degrees of complexity and accuracy: allometric equations, time-energy-budget analyses and thermodynamic models. However, a comparison of their practicability and accuracy was still lacking. Here, we present an overview of these 3 model types, their characteristics, advantages and disadvantages, and areas of application in seabirds. We then investigate their accuracy by using them in parallel for the same dataset, and by comparing outputs with direct measurements (doubly-labelled water technique). We show that, when detailed data are available, time-energy-budget analysis is the best model to accurately predict seabird energy expenditures. Conversely, thermodynamic modelling allows reasonably accurate calculations when field data are scarce, and is therefore ideal to study energetics during the inter-breeding season.
Programme: 388
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BECK P., NILSEN L., JOLY D.,. (2005). Modelling local distribution of an arctic dwarf shrub indicates an important role for remote sensing of snow cover. Remote sensing of environment, 98, 110–121.
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CORBEL Hélène, MORLON Francis, GEIGER Sylvie, GROSCOLAS René, . (2009). State-dependent decisions during the fledging process of king penguin chicks
. Animal behaviour, 78, 829–838.
Abstract: In birds, the chick's physical state at nest departure is critical for survival, especially for seabirds that shift from a terrestrial to a marine life. The timing of this life history transition should therefore be finely tuned by proximate factors reflecting the relative influence of parents and chicks. Using king penguins, Aptenodytes patagonicus, as a model, we investigated how food provisioning and chick developmental status and/or body condition interact with chick fledging behaviour to optimize the physical state at colony departure. During the month preceding colony departure, movements, developmental status and body condition were compared between naturally and experimentally fed chicks. Parents stopped feeding their moulting, obese chick on average 16 days before colony departure and no offspring anorexia was observed. All chicks left their feeding site at the time of moult end, indicating that complete feather development is a prerequisite for departing. The time between moult end and colony departure reduced both intra- and intergroup variation in body condition at departure, suggesting that this condition was optimized in terms of a trade-off between fat stores and buoyancy. After moult end, chicks increased their locomotor activity and energy expenditure, which contributes to the regulation of body condition. Our results indicate that the cessation of parental feeding does not trigger colony departure. Rather, the timing of departure depends on the chick's physical state, regardless of its recent feeding history. Thus, in king penguins, the parental decision to desert the chick seems to reflect a compromise between the offspring's body condition and its developmental status.
Keywords: Actividad, Activité, Activity, Alimentación, Alimentation, Animal jeune, Animal joven, Aptenodytes patagonicus, Aquatic environment, Aves, body condition, Colonia, Colonie, Colony, colony departure, Comportement alimentaire, Condición fisiológica, Condition physiologique, Conducta alimenticia, Conflict, Conflicto, Conflit, Decisión, Descendance, Descendencia, Emplumamiento, Emplumement, Feeding, Feeding behavior, Fledging, food provisioning, king penguin, locomotor activity, Marine environment, Medio acuático, Medio marino, Milieu aquatique, Milieu marin, Molt, moult, Muda, Mue, Parent, parent-offspring conflict, Pariente, Physiological condition, Progeny, Spheniscidae, Vertebrata, Young animal,
Programme: 119
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Claeys Magda, Wang Wan, Vermeylen Reinhilde, Kourtchev Ivan, Chi Xuguang, Farhat Yasmeen, Surratt Jason D, Gmez-Gonzlez Yadian, Sciare Jean, Maenhaut Willy,. (2010). Chemical characterisation of marine aerosol at Amsterdam Island during the austral summer of 2006-2007. Journal of Aerosol Science, 41(1), 13–22.
Abstract: Atmospheric aerosols were collected in separate fine (<2.5 μm) and coarse (>2.5 μm) size fractions in the period December 2006-March 2007 at Amsterdam Island in the southern Indian Ocean. A major objective of the study was to assess biogenic impact on the marine aerosol. The samples were analysed for organic carbon, water-soluble organic carbon, major inorganic ionic species, and organic species, including methanesulphonate (MSA), dicarboxylic acids, and organosulphates. The concentrations of sea salt, non-sea-salt sulphate, and water-soluble and water-insoluble organic matter (WSOM and WIOM) were estimated. Sea salt dominated the composition of the aerosol and accounted for 83% and 91% of the sum of the mass of the four aerosol types in the fine and coarse size fractions, respectively. WSOM, which can serve as a proxy for biogenic secondary organic aerosol (SOA), accounted for only 2.8% of the sum of the mass of the four aerosol types in the fine size fraction. MSA was the dominating organic compound with a median concentration of 47 ng m-3. The organosulphates were characterised as sulphate esters of hydroxyl acids and a dihydroxylaldehyde, which may originate from the oxidation of algal/bacterial unsaturated fatty acid residues. No evidence was found for isoprene SOA.
Keywords: Marine aerosols, Water-soluble organic carbon, Secondary organic aerosol, Organosulphates, Isoprene,
Programme: 414;415
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