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The syntheses of unprecedented bis-triazolyl BODIPY dyes displaying high quantum yields are described. The synthetic approach involves a key alkene metathesis step after templating the two bis-triazolyl dipyrromethenes with Zn, promoting the catenane structure at the expense of the mono-macrocyclic structure. The optical properties of the open form, macrocyclic, and [2]-catenane derivatives are compared. Interestingly, if the fluorescence of both the open and the macrocyclic structure displayed excellent fluorescent properties in dichloromethane, the fluorescence is quenched for the catenane analogue. However, the fluorescence of the catenane can be restored in toluene. A putative explanation for the strong solvent effect is proposed.

International audience; We report a ruthenium(II) bisacetylide complex bearing a photochromic dithienylethene (DTE) acetylide arm and a coordinating bipyridyl on the trans acetylide unit. Its coordination with Yb(TTA)(3) centers (TTA = 2-thenoyltrifluoroacetonate) produces a bimetallic complex in which the dithienylethene isomerization is triggered by both ultraviolet (UV) light absorbed by the DTE unit and 450 nm excitation in a transition of the organometallic moiety. The redox behavior arising from the ruthenium(II) bisacetylide system is fully investigated by cyclic voltammetry and spectroelectrochemistry, revealing a lack of stability of the DTE-closed oxidized state preventing effective redox luminescence switching. On the other hand, the photoswitching of ytterbium(III) near-infrared (NIR) emission triggered by the photochromic reaction is fully operational. The electronic structure of this complex in its different states characterized by strong electronic coupling between the DTE and the ruthenium(II)-based moieties leading to metal-assisted photochromic behavior were rationalized with the help of time-dependent density functional theory (TD-DFT) calculations.

Circularly polarized luminescence activity from new cationic water soluble Sm(iii) and Eu(iii) complexes is triggered by one- and two-photon absorption processes. The Eu(iii) complex is shown to be an efficient NIR-to-RED probe in cellulo.

Photodynamic therapy (PDT) ideally relies on the administration, selective accumulation and photoactivation of a photosensitizer (PS) into diseased tissues. In this context, we report a new heavy-atom-free fluorescent G-quadruplex (G4) DNA-binding PS, named DBI. We reveal by fluorescence microscopy that DBI preferentially localizes in intraluminal vesicles (ILVs), precursors of exosomes, which are key components of cancer cell proliferation. Moreover, purified exosomal DNA was recognized by a G4-specific antibody, thus highlighting the presence of such G4-forming sequences in the vesicles. Despite the absence of fluorescence signal from DBI in nuclei, light-irradiated DBI-treated cells generated reactive oxygen species (ROS), triggering a 3-fold increase of nuclear G4 foci, slowing fork progression and elevated levels of both DNA base damage, 8-oxoguanine, and double-stranded DNA breaks. Consequently, DBI was found to exert significant phototoxic effects (at nanomolar scale) toward cancer cell lines and tumor organoids. Furthermore, in vivo testing reveals that photoactivation of DBI induces not only G4 formation and DNA damage but also apoptosis in zebrafish, specifically in the area where DBI had accumulated. Collectively, this approach shows significant promise for image-guided PDT.

International audience; Synthesis and use of the unprecedented thiochromenocarbazole imide (TCI) for the preparation of printed, large-area and flexible OLEDs.

This paper describes the rationale and the protocol of the first component of the third simulation round of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3a, www.isimip.org) and the associated set of climate-related and direct human forcing data (CRF and DHF, respectively). The observation-based climate-related forcings for the first time include high-resolution observational climate forcings derived by orographic downscaling, monthly to hourly coastal water levels, and wind fields associated with historical tropical cyclones. The DHFs include land use patterns, population densities, information about water and agricultural management, and fishing intensities. The ISIMIP3a impact model simulations driven by these observation-based climate-related and direct human forcings are designed to test to what degree the impact models can explain observed changes in natural and human systems. In a second set of ISIMIP3a experiments the participating impact models are forced by the same DHFs but a counterfactual set of atmospheric forcings and coastal water levels where observed trends have been removed. These experiments are designed to allow for the attribution of observed changes in natural, human and managed systems to climate change, rising CH4 and CO2 concentrations, and sea level rise according to the definition of the Working Group II contribution to the IPCC AR6.

Despite recurrent emphasis on their ecological and economic roles, the importance of high-trophic levels on ocean carbon dynamics, through passive (fecal pellet production, carcasses) and active (vertical migration) processes, is still largely unexplored, notably under climate change scenarios. Additionally, high trophic levels impact the ecosystem dynamics through top-down effects on lower trophic levels, which might change under anthropogenic influence. Here we compare two simulations of a global biogeochemical-ecosystem model with and without feedbacks from large marine animals. We show that these large marine animals affect the evolution of low-trophic level biomasses, hence net primary production and most certainly ecosystem equilibrium, but seem to have little influence on the 21st century anthropogenic carbon uptake under the RCP8.5 scenario. These results provide new insights regarding the expectations for trophic amplification of climate change through the marine trophic chain and regarding the necessity to explicitly represent marine animals in Earth System Models.

Facile access to site-selective hetero-lanthanide molecules will open new avenues in the search of novel photophysical phenomena based on Ln-to-Ln′ energy transfer (ET). This challenge demands strategies to segregate efficiently different Ln metal ions among different positions in a molecule. We report here the one-step synthesis and structure of a pure [YbNdYb] (1) coordination complex featuring short Yb···Nd distances, ideal to investigate a potential distributive (i.e., from one donor to two acceptors) intramolecular ET from one Nd3+ ion to two Yb3+ centers within a well-characterized molecule. The difference in ionic radius is the mechanism allowing to allocate selectively both types of metal ion within the molecular structure, exploited with the simultaneous use of two β-diketone-type ligands. To assist the photophysical investigation of this heterometallic species, the analogues [YbLaYb] (2) and [LuNdLu] (3) have also been prepared. Sensitization of Yb3+ and Nd3+ in the last two complexes, respectively, was observed, with remarkably long decay times, facilitating the determination of the Nd-to-Yb ET within the [YbNdYb] composite. This ET was demonstrated by comparing the emission of iso-absorbant solutions of 1, 2, and 3 and through lifetime determinations in solution and solid state. The comparatively high efficiency of this process corroborates the facilitating effect of having two acceptors for the nonradiative decay of Nd3+ created within the [YbNdYb] molecule., The authors thank the Spanish AEI for grants PGC2018-098630-B-I00 (G.A. and D.A.), PID2020-118329RB-I00 (O.R.), and the Generalitat de Catalunya for an FI-SDUR Grant (2020-FISDU-00492, D.M.), and the ICREA Academia 2018 Prize (G.A.), as well as the Advanced Light Source, which is a DOE Office of Science User Facility operating under contract no. DE-AC02-05CH11231. This work used resources of the ALBA synchrotron through access to beamline 13-XALOC. This study was also supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17.I1) and by Generalitat de Catalunya.

International audience; Because most food processes are fossil fuel-based, many food markets are more or less connected to the oil market. Fishing technology in the high seas being energy-intensive, higher oil prices should affect the fish markets. This research looks at price transmission between Marine Diesel Oil and a global fishery commodity, frozen Skipjack tuna (Katsuwonus pelamis) through a time series analysis combining four different methods to look for possible structural breaks and regime shifts in the relationship (Bai-Perron, Lavielle, Gregory-Hansen, Markov-switching). Our results prove that the long-run equilibrium between both prices is weakening after the turn of the 2010s. Explaining the drivers of change is of great interest for short-term forecast but also to build long-term scenarios where both supply and demand variables are likely to affect tuna markets.; Puisque la plupart des filières agro-alimentaires reposent sur des énergies fossiles, de nombreux marchés alimentaires sont plus ou moins connectés au marché du pétrole. La technologie des pêcheries hauturières étant elle-même intensive en énergie, un prix plus élevé du pétrole devrait se refléter dans le prix du poisson. Cette recherche s'intéresse à la transmission des prix entre le diesel marin et un produit de la pêche global, le listao (Katsuwonus pelamis) congelé, via une analyse de séries temporelles croisant quatre méthodes différentes pour repérer des changements structurels et de régime dans la relation de prix (Bai-Perron, Lavielle, Gregory-Hansen, Markov-switching). Nos résultats montrent que l'équilibre de long terme s'atténue au tournant des années 2010. Expliquer les facteurs de ce changement représente certes un enjeu important pour des prévisions de court-terme, mais permet également de bâtir des scénarios de long-terme où les variables d'offre et de demande sont susceptibles de perturber conjointement les marchés thoniers.

Lanthanide ions have attracted great interest owing to their optical and magnetic properties. Single-molecule magnet (SMM) behavior has been a fascinating science for thirty years. Moreover, chiral lanthanide complexes allow the observation of remarkable circularly polarized luminescence (CPL). However, the combination of both SMM and CPL behaviors in a single molecular system is very rare and deserves attention in the design of multifunctional materials. Four chiral one-dimensional coordination compounds involving 1,1′-Bi-2-naphtol (BINOL)-derived bisphosphate ligands and the Yb(III) centre were synthesized and characterized by powder and single-crystal X-ray diffraction. All the Yb(III)-based polymers displayed field-induced SMM behavior with magnetic relaxation occurring by applying Raman processes and near infrared CPL in the solid state.

International audience; The combination of physical properties sensitive to molecular chirality in a single system allows the observation of fascinating phenomena such as Magneto-Chiral Dichroism (MChD) and Circularly Polarized Luminescence (CPL) having potential applications for optical data readout and display technology. Homochiral monodimensional coordination polymers of YbIII were designed from a 2,15-bis-ethynyl-hexahelicenic scaffold decorated with two terminal 4-pyridyl units. Thanks to the coordination of the chiral organic chromophore to Yb(hfac)3 units, efficient NIR-CPL activity is observed. Moreover, the specific crystal field around the YbIII induces a strong magnetic anisotropy which leads to a slow magnetic relaxation (SMM) and a remarkable room temperature MChD. The MChD-structural correlation is supported by computational investigations.

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene ("aza-DIPY") ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal.

Aza-BODIPYs are an increasingly studied class of fluorophores. They can be seen as an "aza-DIPY" ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. Impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) make them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this red shift seems to be more due to the geometry around the boron/metal than to the nature of the metal.

International audience; The reaction between the 2-(1-(2,6-di(pyrazol-1-yl)-4-methylpyridyl)-4,5-(4,5-bis(propylthio)-tetrathiafulvalenyl)-1H-benzimidazol-2-yl)-pyridine ligand (L), 1 equivalent of Ln(hfac)(3)·2H(2)O/Dy(tta)(3)·2H(2)O (hfac(-) = 1,1,1,5,5,5-hexafluoroacetylacetonate, tta(-) = 2-thenoyltrifluoroacetonate) and M(hfac)(2)·2H(2)O leads to the formation of heteroleptic 3d-4f dinuclear complexes of formula [MLn(hfac)(5)(L)](n) (M(II) = Cd, Zn, Co, Mn, Ni and Ln(III) = Dy, Yb, Nd) and [ZnDy(tta)(2)(hfac)(3)(L)]·(CH(2)Cl(2)). Their X-ray structures reveal that the two coordination sites are occupied by one Ln(III) ion and one M(II) transition metal respectively. The M(II) ions are coordinated to the benzoimidazolylpyridine (bzip) moiety in a N(2)O(4) coordination sphere, while the Ln(III) ions are coordinated to the 2,6-di(pyrazol-1-yl)-4-pyridine (dpp) moiety in a N(3)O(6) surrounding. When Dy(III) ion is used a field-induced Single-Molecule Magnet (SMM) behavior is detected with a magnetic relaxation time slightly dependent to the nature of the vicinal divalent transition metal. On the other hand, when the Yb(III) is used, intense, moderated or quenched (2)F(5/2) → (2)F(7/2) NIR luminescence is observed when the Yb(III) ion is respectively associated with the Zn(II), Mn(II) and Ni(II)/Co(II) ion. The emission intensity can be modulated in function of the metal-to-ligand charge transfer and d-d transition intensities. The replacement of the divalent transition metal by a trivalent lanthanide leads to the formation of heteroleptic 4f-4f’ dinuclear complexes of formula [Ln(2-x)Ln’(x)(hfac)(6)(L)]·a(CH(2)Cl(2))·b(C(6)H(14)) and [Dy(1.11)Nd(0.89)(tta)(3)(hfac)(3)(L)]. The coordination selectivity is based on the radius. Among the 4f-4f’ series, the Dy(III) derivatives displayed such ion in N(2)O(6) eight-coordinated sphere allowing the observation of SMM behavior. The three compounds [Dy(1.21)Nd(0.79)(hfac)(6)(L)]·2(CH(2)Cl(2))·(C(6)H(14)), [Yb(1.04)Nd(0.96)(hfac)(6)(L)] and [YbPr(hfac)(6)(L)] displayed respectively Nd(III), modarated Yb(III) and intense Yb(III) NIR emissions.

International audience; Pelagic fauna is expected to be impacted under climate change according to ecosystem simulations. However, the direction and magnitude of the impact is still uncertain and still not corroborated by observational-based statistical studies. Here we compile a global underwater sonar database and 20 ocean climate projections to predict the future distribution of sound-scattering fauna around the world's oceans. We show that global pelagic fauna will be seriously compromised by the end of the 21 st century, if we continue under the current greenhouse emission scenario. Low and mid latitudes are expected to lose from 3 to 22% of animal biomass due to the expansion of low-productive systems, while higher latitudes would be populated by present-day temperate fauna, supporting conclusions drawn from ecosystem simulations. We further show that strong-mitigation measures to contain global warming below 2°C would reduce these impacts to less than half.

International audience

International audience; New “all-in-one” theranostic systems, combining a magnetic resonance imaging (MRI) contrast agent with a biphotonic photodynamic therapy (2P-PDT) photosensitiser generating cytotoxic singlet oxygen, were envisaged and synthesised. They are based on azamacrocycles, regiospecifically functionalised by two-photon PDT π-conjugated dibromobenzene–picolinate photosensitisers and acetate, able to complex gadolinium(III) and allow an MRI signal. Our approach was to use two different macrocyclic platforms, tacn and pyclen, for modulating simultaneously the structures, properties and solubility of the complexes. Photophysical properties of the ligands and their gadolinium(III) complexes were fully investigated. The Gd3+–pyclen derivative showed the best water solubility and the greatest value of singlet oxygen generation of the series with ΦΔ = 0.53 enabling in vitro studies. The biological PDT activity under mono and biphotonic excitation was evaluated in human breast cancer cells (MCF-7). While a very low dark toxicity was observed, an almost total cell death was induced after only 3 successive irradiations of 1.57 s. Finally, its relaxivity was measured in a DMSO/H2O solvent mixture with r1p = 11.21 and r2p = 24.60 mM−1 s−1 at 3.0 T and T1- and T2-weighted phantom MR images were obtained highlighting a first generation of “all-in-one” PDT/MRI theranostic agents.

International audience; Amino-heptamethines are highly conjugated cationic dyes featuring electronic absorption in the red region and strong nearinfrared (NIR) fluorescence. Unlike their parent chloro-heptamethine cyanines, the substitution of the central position of their polymethine skeleton with an amine confers them a high Stokes shift. This work reports the synthesis of aminoheptamethines and the investigation of their optical properties, including two-photon absorption in the NIR and shortwave infrared (SWIR) ranges, which has been overlooked for such chromophores so far. Their structures were tailored, introducing selected substitutuents on the indolenine moieties to modulate their hydrophobic/hydrophilic balance and investigate their potential as NIR-to-NIR two-photon probes for the bio-imaging of living cells.

International audience; In addition to the already described ligand L4a, two pyclen-based lanthanide chelators, L4b and L4c, bearing two specific picolinate two-photon antennas (tailor-made for each targeted metal) and one acetate arm arranged in a dissymmetrical manner, have been synthesized, to form a complete family of lanthanide luminescent bioprobes: [EuL4a], [SmL4a], [YbL4b], [TbL4c], and [DyL4c]. Additionally, the symmetrically arranged regioisomer L4a′ was also synthesized as well as its [EuL4a′] complex to highlight the astonishing positive impact of the dissymmetrical N-distribution of the functional chelating arms. The investigation clearly shows the high performance of each bioprobe, which, depending on the complexed lanthanide, could be used in various applications. Each presents high brightness, quantum yields, and lifetimes. Staining of the complexes into living human breast cancer cells was observed. In addition, in vivo two-photon microscopy was performed for the first time on a living zebrafish model with [EuL4a]. No apparent toxicity was detected on the growth of the zebrafish, and images of high quality were obtained.

Through the preparation and characterization of five new derivatives, the regioselective mono and di, homo and hetero, halogenation of the benzothioxanthene (BTXI) core is demonstrated herein. All structurally solved by X-ray crystallography, these complementary functionalized building blocks open doors to the design of new symmetrical and asymmetrical π-conjugated systems based on this promising but still under-explored rylene.

In this study, an original aza-BODIPY system comprising two Gd3+ complexes has been designed and synthesized for magnetic resonance imaging/optical imaging application, by functionalization of the boron center. This strategy enabled to obtain a positively-charged bimodal probe, which displays an increased water-solubility, optimized photophysical properties in the near-infrared region, and very promising relaxometric properties. The absorption and emission wavelengths are 705 and 741 nm respectively, with a quantum yield of around 10 % in aqueous media. Moreover, the system does not produce singlet oxygen upon excitation, which would be toxic for tissues. The relaxivity obtained is high at intermediate fields (16.1 mM-1.s-1 at 20 MHz and 310 K) and competes with that of bigger or more rigid systems. A full relaxometric and 17O NMR study and fitting of the data using the Lipari-Szabo approach showed that this high relaxivity can be explained by the size of the system and the presence of some small aggregates. These optimized photophysical and relaxometric properties highlight the potential use of such systems for future bimodal imaging studies.

Ocean net primary production (NPP) consists of CO2 fixation by marine phytoplankton and hence supports most marine food webs, fisheries and ocean carbon sequestration. Recent Earth System Model (ESM) projections of NPP changes under global warming scenarios, performed as part of the 6th phase of Coupled Model Intercomparison Project (CMIP6), show large uncertainty both in the magnitude and spatial distribution of NPP, which may have consequences for assessing ecosystem impacts and ocean carbon uptake. NPP uncertainty has increased since the previous intercomparion project (CMIP5), and likely does not even capture the full range of possible outcomes due to the general simplicity of ecosystem parameterizations employed in ESMs and the failure to account for non-climate drivers. Here, we exploit the full set of ESM projections from CMIP6, documenting NPP uncertainties and identifying certain physical and biogeochemical mechanisms that give rise to these uncertainties. We then use different versions of the IPSL ESM to explore (1) the specific role of N-fixation by diazotrophs in the upper ocean and (2) the influence of coupling to higher trophic levels in shaping the response of NPP, marine ecosystems and biogeochemistry to anthropogenic climate change. We show that the response of N-fixation to global warming is a key driver of NPP projection uncertainties in the coming decades, even determining the sign of the global NPP response. Despite contrasting projections of future NPP, all our model versions simulate similar and significant reductions in planktonic biomass. This suggests that plankton biomass may be a more robust indicator than NPP of the potential impact of anthropogenic climate change on marine ecosystems across models. In a second step, we show that an explicit coupling to higher trophic levels modifies the response of lower trophic levels (plankton) and shifts the ecosystem equilibrium, but seems to have limited influence on 21st century anthropogenic carbon uptake under the RCP8.5 high emissions scenario. These results provide new insights regarding the expectations for trophic amplification of climate impacts through the marine food chain and regarding the necessity to explicitly represent marine animals in Earth System Models.

Many decisions in the field of agriculture, forestry and/or hydrology can get profit from seasonal forecast. However, the skill of such forecast is a critical issue to promote their use in operational context and get profitable decisions. If many methods to assess meteorological forecast performances are available, they are mostly implemented on raw climate variables, while their implementation in sectorial application remains limited to some case studies. In this study a wide range of indicators covering most of the decision-making needs in agriculture, forestry and in some extent to hydrology were considered. These indicators are either direct climate variables, a combination of climate variables, or variables calculated by dynamic models (e.g. a crop model). The study was implemented in southern France using the Méteo-France system 6 1993-2016 hindcast, downscaled using the UERRA reanalysis and the ADAMONT methods available in CS-Tools R package developed in the frame of the MEDSCOPE project. These computed indicators need various climate variables as wind speed, radiation and air humidity while most of the downscaling methods were designed for air temperature and precipitation. The main results are the following.We showed that all variables led to comparable level of accuracy. Seasonal forecasts provide added value compared to climatological forecasts with Brier Skill Scores between 0.05 and 0.20. The predictability of the number of rainy days or the number of days with temperature above a threshold is comparable to those of the corresponding scalar quantities such as cumulative precipitation or mean air temperature. However seasonal forecast of extreme events such as heat waves or drought episodes was not possible. Indicators combining several climatic information such as potential evapotranspiration or fire weather index have comparable predictability than the individual climate variables used in the calculation. With indicators based on dynamic models, the memory effect, i.e. the effect of the system state at the beginning of the forecast period, has a strong impact on the skill scores. We propose a methodology based on an ANOVA to qualify this memory effect by using the F-value. It is shown that when the memory effect is strong (F-value >10) the seasonal forecast does not bring any added value compared to the climatological forecast. An evaluation of the interest of a seasonal forecast in a decision-making framework was carried out by an economic approach. We have based our analysis on the decision making based on the forecast of an event. We show that there is a generic relationship between the AUC score and the gain from the forecast. We show that this relationship depends on the frequency of the decision event, the rarer the event the higher the AUC value must be to have a profitable decision. In our case, a decision based on the detection of a tercile leads to a profitable decision in more than half of the indicators while no indicator leads to a profitable decision when it is based on the detection of a quintile.

International audience; The fast relaxation processes in the excited electronic states of functionalized aza-boron-dipyrromethene (aza-BODIPY) derivatives (1-4) were investigated in liquid media at room temperature, including the linear photophysical, photochemical, and nonlinear optical (NLO) properties. Optical gain was revealed for nonfluorescent derivatives 3 and 4 in the near infrared (NIR) spectral range under femtosecond excitation. The values of two-photon absorption (2PA) and excited-state absorption (ESA) cross-sections were obtained for 1-4 in dichloromethane using femtosecond Z-scans, and the role of bromine substituents in the molecular structures of 2 and 4 is discussed. The nature of the excited states involved in electronic transitions of these dyes was investigated using quantum-chemical TD-DFT calculations, and the obtained spectral parameters are in reasonable agreement with the experimental data. Significant 2PA (maxima cross-sections ∼2000 GM), and large ESA cross-sections ∼10(-20) m(2) of these new aza-BODIPY derivatives 1-4 along with their measured high photostability reveal their potential for photonic applications in general and optical limiting in particular.

Place: Lausanne Publisher: Frontiers Media Sa WOS:000760695700001; International audience; Pelagic fish communities are shaped by bottom-up and top-down processes, transport by currents, and active swimming. However, the interaction of these processes remains poorly understood. Here, we use a regional implementation of the APex ECOSystem Model (APECOSM), a mechanistic model of the pelagic food web, to investigate these processes in the California Current, a highly productive upwelling system characterized by vigorous mesoscale circulation. The model is coupled with an eddy-resolving representation of ocean currents and lower trophic levels, and is tuned to reproduce observed fish biomass from fisheries independent trawls. Several emergent properties of the model compare realistically with observations. First, the epipelagic community accounts for one order of magnitude less biomass than the vertically migratory community, and is composed by smaller species. Second, the abundance of small fish decreases from the coast to the open ocean, while the abundance of large fish remains relatively uniform. This in turn leads to flattening of biomass size-spectra away from the coast for both communities. Third, the model reproduces a cross-shore succession of small to large sizes moving offshore, consistent with observations of species occurrence. These cross-shore variations emerge in the model from a combination of: (1) passive offshore advection by the mean current, (2) active swimming toward coastal productive regions to counterbalance this transport, and (3) mesoscale heterogeneity that reduces the ability of organisms to return to coastal waters. Our results highlight the importance of passive and active movement in structuring the pelagic food web, and suggest that a representation of these processes can help to improve the realism in simulations with marine ecosystem models.

International audience; A series of tris-dipicolinate europium complexes featuring different complexes has been prepared, and their photophysical study has been performed in the solid state highlighting the crucial role of second sphere water molecules. The non-radiative deactivation constant (k nr ) varies significantly with the number of interstitial water molecules and their distance to the europium emitting center. The complex (NBu 4 ) 3 [Eu(DPA) 3 ], featuring the most lipophilic cation, exhibits excellent solubility and remarkable photophysical properties in aprotic solvents

Cry11Aa and Cry11Ba are the two most potent toxins produced by mosquitocidal Bacillus thuringiensis subsp. israelensis and jegathesan, respectively. The toxins naturally crystallize within the host; however, the crystals are too small for structure determination at synchrotron sources. Therefore, we applied serial femtosecond crystallography at X-ray free electron lasers to in vivo-grown nanocrystals of these toxins. The structure of Cry11Aa was determined de novo using the single-wavelength anomalous dispersion method, which in turn enabled the determination of the Cry11Ba structure by molecular replacement. The two structures reveal a new pattern for in vivo crystallization of Cry toxins, whereby each of their three domains packs with a symmetrically identical domain, and a cleavable crystal packing motif is located within the protoxin rather than at the termini. The diversity of in vivo crystallization patterns suggests explanations for their varied levels of toxicity and rational approaches to improve these toxins for mosquito control.