Activity of EGFR Tyrosine Kinase Inhibitors in NSCLC With Refractory Leptomeningeal Metastases

International audienc

Initial examples of the SOLUS multimodal potential

We present initial evidence of the SOLUS potential for the multimodal non-invasive diagnosis of breast cancer by describing the correlation between optical and standard radiological data and analyzing a case study

Contributions des vagues dans les surcotes de tempête en zones littorales

Les surcotes et submersions marines associées aux tempêtes peuvent entraîner des catastrophes majeures. Les surcotes correspondent à une élévation temporaire du niveau moyen de la mer, induite par les gradients de pression atmosphérique, le vent et les vagues. La dissipation des vagues en zone littorale génère une augmentation du niveau moyen à la côte, le wave setup, qui contribue aux surcotes. Cette thèse de doctorat examine les contributions des vagues aux surcotes, notamment le wave setup, dans différents milieux littoraux en combinant l’analyse de données in-situ et la modélisation numérique à haute résolution. En premier lieu, la contribution du déferlement de vagues de tempête à l’embouchure de deux environnements abrités des vagues est étudiée. Les résultats montrent que le wave setup généré représente 40% du pic de la surcote dans l'Estuaire de l'Adour et 23% dans le Bassin d'Arcachon. La dissipation des vagues et la circulation moyenne induite sont ensuite analysées sur un estran rocheux. La forte rugosité de l’estran a deux effets antagonistes sur le wave setup : (1) les vagues sont fortement dissipées par frottement au fond, ce qui réduit le wave setup par rapport à un fond sableux ; (2) la circulation induite par les vagues sur un fond rugueux augmente le wave setup. Enfin, la dissipation des vagues et le wave setup sont examinés sur un pré salé. Lors de l’épisode de mer de vent étudié, la végétation halophyte du pré salé explique 65% de la dissipation des vagues, ce qui réduit le wave setup par rapport à un cas sans végétation. De nouvelles mesures sont nécessaires pour analyser l'effet sur le wave setup des non-linéarités des vagues sur un fond végétalisé.Storm surges and associated coastal flooding can result in major catastrophes. Storm surges correspond to a temporary rise in sea level driven by atmospheric pressure gradients, wind and short waves. In particular, the dissipation of short waves in the nearshore drives a mean water level increase, the wave setup, which contributes to storm surges. This PhD thesis examines the contributions of short waves to storm surges, notably the wave setup, in contrasting coastal environments. To that end, the analysis of field data is combined with high-resolution numerical modelling. First, this work investigates the contribution to storm surges of very large storm waves breaking at the inlet of two wave-sheltered environments. The results indicate that the resulting wave setup contributes up to 40% and 23% to the storm surge peak in the Adour Estuary and the Arcachon Lagoon respectively. Second, the dissipation of storm waves and the resulting depth-varying circulation are analysed at a rock shore platform. Two counteracting effects of the high bottom roughness on the wave setup are identified: (1) waves suffer a strong dissipation by bottom friction, which reduces the wave setup compared to a smooth bottom; (2) the wave-induced circulation over a rough bottom enhances the wave setup. Lastly, waves and wave setup dynamics are investigated on a salt marsh. During the studied wind sea event, the halophytic vegetation of the salt marsh accounts for 65% of the wave dissipation, which reduces the wave setup compared to a case without vegetation. New field measurements on salt marshes are needed to explore the effect of wave non-linearities on the wave setup in vegetation fields

Contributions des vagues dans les surcotes de tempête en zones littorales

Storm surges and associated coastal flooding can result in major catastrophes. Storm surges correspond to a temporary rise in sea level driven by atmospheric pressure gradients, wind and short waves. In particular, the dissipation of short waves in the nearshore drives a mean water level increase, the wave setup, which contributes to storm surges. This PhD thesis examines the contributions of short waves to storm surges, notably the wave setup, in contrasting coastal environments. To that end, the analysis of field data is combined with high-resolution numerical modelling. First, this work investigates the contribution to storm surges of very large storm waves breaking at the inlet of two wave-sheltered environments. The results indicate that the resulting wave setup contributes up to 40% and 23% to the storm surge peak in the Adour Estuary and the Arcachon Lagoon respectively. Second, the dissipation of storm waves and the resulting depth-varying circulation are analysed at a rock shore platform. Two counteracting effects of the high bottom roughness on the wave setup are identified: (1) waves suffer a strong dissipation by bottom friction, which reduces the wave setup compared to a smooth bottom; (2) the wave-induced circulation over a rough bottom enhances the wave setup. Lastly, waves and wave setup dynamics are investigated on a salt marsh. During the studied wind sea event, the halophytic vegetation of the salt marsh accounts for 65% of the wave dissipation, which reduces the wave setup compared to a case without vegetation. New field measurements on salt marshes are needed to explore the effect of wave non-linearities on the wave setup in vegetation fields.Les surcotes et submersions marines associées aux tempêtes peuvent entraîner des catastrophes majeures. Les surcotes correspondent à une élévation temporaire du niveau moyen de la mer, induite par les gradients de pression atmosphérique, le vent et les vagues. La dissipation des vagues en zone littorale génère une augmentation du niveau moyen à la côte, le wave setup, qui contribue aux surcotes. Cette thèse de doctorat examine les contributions des vagues aux surcotes, notamment le wave setup, dans différents milieux littoraux en combinant l’analyse de données in-situ et la modélisation numérique à haute résolution. En premier lieu, la contribution du déferlement de vagues de tempête à l’embouchure de deux environnements abrités des vagues est étudiée. Les résultats montrent que le wave setup généré représente 40% du pic de la surcote dans l'Estuaire de l'Adour et 23% dans le Bassin d'Arcachon. La dissipation des vagues et la circulation moyenne induite sont ensuite analysées sur un estran rocheux. La forte rugosité de l’estran a deux effets antagonistes sur le wave setup : (1) les vagues sont fortement dissipées par frottement au fond, ce qui réduit le wave setup par rapport à un fond sableux ; (2) la circulation induite par les vagues sur un fond rugueux augmente le wave setup. Enfin, la dissipation des vagues et le wave setup sont examinés sur un pré salé. Lors de l’épisode de mer de vent étudié, la végétation halophyte du pré salé explique 65% de la dissipation des vagues, ce qui réduit le wave setup par rapport à un cas sans végétation. De nouvelles mesures sont nécessaires pour analyser l'effet sur le wave setup des non-linéarités des vagues sur un fond végétalisé

Cross‐Shore Distribution of the Wave‐Induced Circulation Over a Dissipative Beach Under Storm Wave Conditions

International audienceThis study explores the spatial distribution and the driving mechanisms of the wave-induced cross-shore flow within the shoreface and surf zone of a dissipative beach. Unpublished results from a field campaign carried out in early 2021 under storm wave conditions are presented and compared with the predictions from a state-of-the-art phase-averaged three-dimensional circulation modeling system based on the vortex force formalism. Under storm wave conditions, the cross-shore flow is dominated by a strong seaward-directed current in the lower part of the water column. The largest current velocities of this return current are located in the surf zone, where the dissipation by depth-induced breaking is most intense, but offshore-directed velocities up to 0.25 m/s are observed as far as 4 km from the shoreline (≃12 m-depth). Numerical experiments further highlight the key control exerted by non-conservative wave forces and wave-enhanced mixing on the cross-shore flow across a transition zone, where depth-induced breaking, whitecapping, and bottom friction all significantly contribute to the wave energy dissipation. Under storm conditions, this transition zone extended almost 6 km offshore and the cross-shore Lagrangian circulation shows a strong seaward-directed jet in the lower part of the water column, whose intensity progressively decreases offshore. In contrast, the surf zone edge appears clearly delimited under fair weather conditions and the seaward-directed current is weakened by a near bottom shoreward-directed current associated with wave bottom streaming in the shoaling region, such that the clockwise Lagrangian overturning circulation is constrained by an additional anti-clockwise overturning cell at the surf zone edg

Potential for the Production of Carotenoids of Interest in the Polar Diatom Fragilariopsis cylindrus

International audienceCarotenoid xanthophyll pigments are receiving growing interest in various industrial fields due to their broad and diverse bioactive and health beneficial properties. Fucoxanthin (Fx) and the inter-convertible couple diadinoxanthin–diatoxanthin (Ddx+Dtx) are acknowledged as some of the most promising xanthophylls; they are mainly synthesized by diatoms (Bacillariophyta). While temperate strains of diatoms have been widely investigated, recent years showed a growing interest in using polar strains, which are better adapted to the natural growth conditions of Nordic countries. The aim of the present study was to explore the potential of the polar diatom Fragilariopsis cylindrus in producing Fx and Ddx+Dtx by means of the manipulation of the growth light climate (daylength, light intensity and spectrum) and temperature. We further compared its best capacity to the strongest xanthophyll production levels reported for temperate counterparts grown under comparable conditions. In our hands, the best growing conditions for F. cylindrus were a semi-continuous growth at 7 °C and under a 12 h light:12 h dark photoperiod of monochromatic blue light (445 nm) at a PUR of 11.7 μmol photons m−2 s−1. This allowed the highest Fx productivity of 43.80 µg L−1 day−1 and the highest Fx yield of 7.53 µg Wh−1, more than two times higher than under ‘white’ light. For Ddx+Dtx, the highest productivity (4.55 µg L−1 day−1) was reached under the same conditions of ‘white light’ and at 0 °C. Our results show that F. cylindrus, and potentially other polar diatom strains, are very well suited for Fx and Ddx+Dtx production under conditions of low temperature and light intensity, reaching similar productivity levels as model temperate counterparts such as Phaeodactylum tricornutum. The present work supports the possibility of using polar diatoms as an efficient cold and low light-adapted bioresource for xanthophyll pigments, especially usable in Nordic countries

The contribution of short-wave breaking to storm surges: The case Klaus in the Southern Bay of Biscay

This study investigates the contribution of short-wave breaking to storm surges through a high-resolution hindcast of the sea state and storm surge associated with the extra-tropical storm Klaus. This storm made landfall in January 2009 in the Southern Bay of Biscay and produced the largest storm surges observed in this region over the last 20 years, with 1.70 m in the Arcachon Lagoon and 1.10 m in the Adour Estuary. A fully-coupled 3D modelling system, which uses a vortex force formalism to represent wave–current interactions, is applied with a spatial resolution down to 35 m in the surf zones in order to properly compute the wave-induced setup. Modelling results reveal that the wave setup contributes by up to 40 % and 23 % to the storm surge peak in the Adour Estuary and the Arcachon Lagoon respectively. Accounting for wave forces in the circulation model improves storm surge predictions by 50 to 60 %. This is explained by the dominant role played by wave forces in the momentum balance at the inlets under storm waves. Numerical experiments further reveal that the wave-induced setup can be tidally-modulated, although this phenomenon seems to be site-specific. Finally, a sensitivity analysis highlights the importance of the model grid resolution in the surf zones to correctly resolve the wave setup along open-ocean coasts. Inside the lagoon, the storm surge and wave setup are less sensitive to the grid resolution while tidal propagation cannot be accurately represented with a resolution of 1000 m, which is typically used in operational storm surge forecast