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The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal time scales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean, and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea–ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate.This article is part of the theme issue ‘Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities’.

Operated since the end of 2009, the European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) satellite mission is the first orbiting radiometer that collects regular and global observations from space of two Essential Climate Variables of the Global Climate Observing System : Sea Surface Salinity (SSS) and Soil Moisture. The National Aeronautics and Space Administration (NASA) Aquarius mission, with the primary objective to provide global SSS measurements from space operated from mid-2011 to mid-2015. NASA's Soil Moisture Active-Passive (SMAP) mission, primarily dedicated to soil moisture measurements, but also monitoring SSS, has been operating since early 2015. The primary sensors on board these three missions are passive microwave radio-meters operating at 1.4 GHz (L-band). SSS is retrieved from radiometer measurements of the sea surface brightness temperature (TB). In this paper, we first provide a historical review of SSS remote sensing with passive L-band radiometry beginning with the discussions of measurement principles, technology, sensing characteristicsand complementarities of the three afore mentioned missions. The assessment of satellite SSS products is then presented in terms of individual mission characteristics, common algorithms, and measurement uncertainties, including the validation versus in situ data, and, the consideration of sampling differences between satellite SSS and in situ salinity measurements. We next review the major scientific achievements of the combined first 10 years of satellite SSS data, including the insights enabled by these measurements regarding the linkages of SSS with the global water cycle, climate variability, and ocean biochemistry. We also highlight the new ability provided by satellites to monitor mesoscale and synoptic-scale SSS features and to advance our understanding of SSS'role in air-sea interactions, constraining ocean models, and improving seasonal predictions. An overview of satellite SSS observation highlights during this first decade and upcoming challenges are then presented.

Monsoon rain and rivers bring large freshwater input to the Northern Bay of Bengal (BoB), yielding low Sea Surface Salinity (SSS) after the monsoon. The resulting sharp upper-ocean salinity stratification is thought to influence tropical cyclones intensity and biological productivity by inhibiting vertical mixing. Despite recent progresses, the density of in situ data is far from sufficient to monitor the BoB SSS variability, even at the seasonal timescale. The advent of satellite remotely-sensed SSS (SMOS, Aquarius, SMAP) offers a unique opportunity to provide synoptic maps of the BoB SSS every similar to 8 days. Previous SMOS SSS retrievals did not perform well in the BoB. Here, we show that improved systematic error corrections and quality control procedures yield a much better performance of the new "debiased v4" CATDS level-3 SSS from SMOS (similar to 0.8 correlation, 0.04 bias and 0.64 root-mean-square difference to more than 28,000 collocated in situ data points over 2010-2019). The SMOS product now performs equivalently to Aquarius, and is slightly inferior to SMAP over the BoB. In particular, SMAP and SMOS are able to capture salinity variations close to the east coast of India (r > 0.8 within 75-150 km of the coast). They thus capture the seasonal freshening there, associated with equatorward advection of the Northern BoB low-salinity water by the East Indian Coastal Current (EICC) after the summer monsoon. The 10-year long SMOS record further allows to describe the BoB interannual SSS variability, which is strongest in boreal fall in relation with the Indian Ocean Dipole (IOD). Positive IOD events induce a weakening of the southward export of freshwater by the EICC, and hence negative SSS anomalies in the Northern BoB and positive ones along the East Indian coast. This confirms results from earlier studies based on modelling, sparse in situ data, or shorter satellite records, but this time from a 10-year long SSS record. Overall, our study indicates that the new SMOS retrieval can be confidently used to monitor the BoB SSS and to study its mechanisms. We end by a brief description of the BoB SSS anomalies associated with the extreme 2019 IOD event and highlight the very good performance over the BoB of a new multi-satellite product developed by the European Space Agency merging SMOS, Aquarius and SMAP data.

The signature of westward propagating mesoscale eddies in sea surface salinity (SSS) is analyzed for the tropical Pacific by collocating 7years (2010-2016) of Soil Moisture and Ocean Salinity SSS satellite data with coherent mesoscale eddies automatically identified and tracked from altimetry-derived sea level anomalies. First, the main characteristics of the long-lived coherent eddies are inferred from sea level anomalies maps. Then, the mean signature of the mesoscale eddies on SSS is depicted for the whole tropical Pacific before focusing in regions centered around the central and eastern parts of the tropical North Pacific. In these areas, composite analyses based on thousands of eddies reveal regionally dependent eddy impacts with opposite SSS anomalies for cyclonic and anticyclonic eddies. In the central region, where the largest meridional SSS large-scale gradients and smallest eddy amplitudes are observed, results show dipole-like SSS changes with maximum anomalies on the leading edge of the composite eddy. In contrast, in the eastern region, where the largest near-surface vertical salinity gradients and largest eddy amplitudes are observed, the composite eddy shows monopole-like SSS changes with maximum anomalies near the composite eddy center. These distinct dipole/monopole SSS patterns suggest the dominant role of horizontal advection and vertical processes in the central and eastern regions, respectively. Other possible explanations, notably one involving the contrasted eddy amplitudes of the two regions, are discussed. Plain Language Summary Sea surface salinity (SSS) is an Essential Climate Variable needed to improve our knowledge of the Earth's water cycle and climate. SSS has proven to be valuable for improving estimates of evaporation minus precipitation (E-P) budgets, describing and understanding climate variability at seasonal to decadal time scales, testing physical processes, assessing numerical model skills, quantifying the role of salinity on sea level change, improving El Nino prediction lead time, and quantifying the ocean-atmosphere CO2 exchanges. Very few studies have, however, focused on what we call small-scale (that is mainly eddies of the order of 50- to 300-km radius) SSS changes in the open ocean, mainly due to the lack of high-resolution measurements. Relying on unprecedented satellite measurements of SSS, the present study shows how eddies in the tropical Pacific can modify the spatial distribution of SSS. We suggest that these modifications are likely due (i) to the rotational sense of the eddies, which move SSS horizontally, and (ii) to their capability to move or mix waters up and down while rotating.

The availability of nutrients in the mixed layer is the main limitation to organic carbon biological production in the tropical regions. In this paper, we investigate the potential role of internal waves at promoting the development of biological activity on a PIRATA mooring at 6 degrees S, 10 degrees W. This mooring is located above the Mid-Atlantic Ridge where we observe strong internal waves. Using a one-dimensional physical and biogeochemical coupled model, we simulate dissolved inorganic carbon (DIC). Providing the influence of vertical advection and turbulent diapycnal diffusivity are (it is vertical advection + turbulent dipycnal mixing) accounted for, we find that this model provides a good fit with observed in situ CO2 fugacity (fCO(2)). Main effect of internal waves is to rapidly increase the DIC, thus the fCO(2) and the nutrients in the mixed layer. The latter induce progressive development of biological activity leading to gradual DIC decrease. Our study highlights the importance of correctly taking into account the effect of internal waves in tropical regions.

National audience; Volet participation du projet AMELI (Analyse Multi-Échelle des Lisières) : croiser expertises techniques, scientifiques et habitantes, pour cartographier ensemble le bocage bressuirais. Une démarche en trois séquences, des représentations alternatives des continuités écologiques. Le projet AMELI comporte également un volet écologie et un volet information géographique.

The impact of the ocean surface roughness on the ocean L-band emissivity is investigated using simultaneous airborne measurements from an L-band radiometer (CAROLS) and from a C-band scatterometer (STORM) acquired in the Gulf of Biscay (off-the French Atlantic coasts) in November 2010. Two synergetic approaches are used to investigate the impact of surface roughness on the L-band brightness temperature (Tb). First, wind derived from the scatterometer measurements is used to analyze the roughness contribution to Tb as a function of wind and compare it with the one simulated by SMOS and Aquarius roughness models. Then residuals from this mean relationship are analyzed in terms of mean square slope derived from the STORM instrument. We show improvement of new radiometric roughness models derived from SMOS and Aquarius satellite measurements in comparison with prelaunch models. Influence of wind azimuth on Tb could not be evidenced from our data set. However, we point out the importance of taking into account large roughness scales (>20 cm) in addition to small roughness scale (5 cm) rapidly affected by wind to interpret radiometric measurements far from nadir. This was made possible thanks to simultaneous estimates of large and small roughness scales using STORM at small (7–16°) and large (30°) incidence angles.

In the present paper we report the genomic organization of the human histamine H3-receptor gene, which consists of four exons spanning 5.5 kb on chromosome 20. Using PCR, six alternative splice variants of the H3 receptor were cloned from human thalamus. These variants were found to be coexpressed in human brain, but their relative distribution varied in a region-specific manner. These isoforms displayed either a deletion in the putative second transmembrane domain (TM), H3(DeltaTM2, 431aa) or a variable deletion in the third intracellular loop (i3), H3(Deltai3, 415aa), H3(Deltai3, 365aa), H3(Deltai3, 329aa) and H3(DeltaTM5+Deltai3, 326aa). In order to determine the biological role of the H3 receptor variants compared with the 'original' H3(445aa) receptor, three isoforms, namely H3(445aa), H3(DeltaTM2, 431aa) and H3(Deltai3, 365aa), were expressed in CHO cells and their pharmacological properties were investigated. Binding studies showed that H3(DeltaTM2, 431aa) transiently expressed in CHO cells was unable to bind [125I]iodoproxyfan, whereas both the H3(445aa) and H3(Deltai3, 365aa) receptors displayed a high affinity for [125I]iodoproxyfan [K(d)=28+/-5 pM (n=4) and 8+/-1 pM (n=5) respectively]. In addition, H3(Deltai3, 365aa) possessed the same pharmacological profile as the H3(445aa) receptor. However, in CHO cells expressing H3(Deltai3, 365aa), H3 agonists did not inhibit forskolin-induced cAMP production, stimulate [35S]guanosine 5'-[gamma-thio]triphosphate ([35S]GTP[S]) binding or stimulate intracellular Ca(2+) mobilization. Therefore the 80-amino-acid sequence located at the C-terminal portion of i3 plays an essential role in H3 agonist-mediated signal transduction. The existence of multiple H3 isoforms with different signal transduction capabilities suggests that H3-mediated biological functions might be tightly regulated through alternative splicing mechanisms.

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International audience; De novo tumors in renal allografts are rare and their prevalence is underestimated. We therefore analyzed renal cell carcinomas arising in renal allografts through a retrospective French renal transplant cohort. We performed a retrospective, multicentric survey by sending questionnaires to all French kidney transplantation centers. All graft tumors diagnosed after transplantation were considered as de novo tumors. Thirty-two centers participated in this study. Seventy-nine tumors were identified among 41 806 recipients (Incidence 0.19%). Patients were 54 men and 25 women with a mean age of 47 years old at the time of diagnosis. Mean tumor size was 27.8 mm. Seventy-four (93.6%), 53 (67%) and 44 tumors (55.6%) were organ confined (T1-2), low grade (G1-2) and papillary carcinomas, respectively. Four patients died of renal cell carcinomas (5%). The mean time lapse between transplantation and RCC diagnosis was 131.7 months. Thirty-five patients underwent conservative surgery by partial nephrectomy (n = 35, 44.3%) or radiofrequency (n = 5; 6.3%). The estimated 5 years cancer specific survival rate was 94%. Most of these tumors were small and incidental. Most tumors were papillary carcinoma, low stage and low grade carcinomas. Conservative treatment has been preferred each time it was feasible in order to avoid a return to dialysis.

The interannual variability of the CO2 partial pressure (pCO2oc) in the surface layer of the east equatorial Pacific Ocean near 100°W is studied and compared with the sea surface temperature (SST) monitored from satellites. This variability is shown to be correlated with the SST anomaly rather than with the temperature itself. The pCO2oc variability is related to the variability of the upwelling systems (the equatorial upwelling and the upwelling along the American coast), the main influence being from the coastal upwelling via the surface water advected from the east. A method is derived to interpolate the pCO2oc measurements using the SST satellite measurements. By combining the result with the exchange coefficient (K) deduced from the wind speed provided by satellite borne instruments we deduce the air–sea CO2 flux and for the 1st time we monitor continuously its temporal evolution. The variability of this flux is mainly due to the variability of K, with a clear seasonal variation. The flux obtained using the Liss and Merlivat (1986) relationship averaged from April 1985 to June 1997 in the region 97.5°−107.5°W 0–5°S is 1.67 mole m−2 yr−1 of CO2 leaving the ocean with an estimated accuracy of 30%.DOI: 10.1034/j.1600-0889.1999.t01-1-00013.x

In order to determine the seasonal and interannual variability of the CO2 released to the atmosphere from the equatorial Pacific, we have developed pCO2-temperature relationships based upon shipboard oceanic CO2 partial pressure measurements, pCO2, and satellite sea surface temperature, SST, measurements. We interpret the spatial variability in pCO2 with the help of the SST imagery. In the eastern equatorial Pacific, at 5°S, pCO2 variations of up to 100 μatm are caused by undulations in the southern boundary of the equatorial upwelled waters. These undulations appear to be periodic with a phase and a wavelength comparable to tropical instability waves, TIW, observed at the northern boundary of the equatorial upwelling. Once the pCO2 signature of the TIW is removed from the Alize II cruise measurements in January 1991, the equatorial pCO2 data exhibit a diel cycle of about 10 matm with maximum values occurring at night. In the western equatorial Pacific, the variability in pCO2 is primarily governed by the displacement of the boundary between warm pool waters, where air–sea CO2 fluxes are weak, and equatorial upwelled waters which release high CO2 fluxes to the atmosphere. We detect this boundary using satellite SST maps. East of the warm pool, ΔP is related to SST and SST anomalies. The 1985–97 CO2 flux is computed in a 5° wide latitudinal band as a combination of ΔP and CO2 exchange coefficient, K, deduced from satellite wind speeds, U. It exhibits up to a factor 2 seasonal variation caused by K-seasonal variation and a large interannual variability, a factor 5 variation between 1987 and 1988. The interannual variability is primarily driven by displacements of the warm pool that makes the surface area of the outgassing region variable. The contribution of ΔP to the flux variability is about half the contribution of K. The mean CO2 flux computed using either the Liss and Merlivat (1986) or the Wanninkhof (1992) K–U parametrization amounts to 0.11 GtC yr−1 or to 0.18 GtC yr−1, respectively. The error in the integrated flux, without taking into account the uncertainty on the K–U parametrization, is less than 31%.DOI: 10.1034/j.1600-0889.1999.00025.x

International audience; SMOS, a L Band radiometer using aperture synthesis to achieve a good spatial resolution, was successfully launched on November 2, 2009. It was developed and made under the leadership of the European Space Agency (ESA) as an Earth Explorer Opportunity mission. It is a joint program with the Centre National d'Etudes Spatiales (CNES) in France and the Centro para el Desarrollo Teccnologico Industrial (CDTI) in Spain. SMOS carries a single payload, an L band 2D interferometric, radiometer in the 1400-1427 MHz h protected band. This wavelength penetrates well through the vegetation and the atmosphere is almost transparent enabling to infer both soil moisture and vegetation water content over land and sea surface salinity over the oceans. SMOS achieves an unprecedented spatial resolution of 50 km at L-band maximum (43 km on average) with multi angular-dual polarized (or fully polarized) brightness temperatures over the globe and with a revisit time smaller than 3 days. SMOS as been now acquiring data for over one year after the end of the commissioning phase. The data quality exceeds what was expected, showing very good sensitivity and stability. The data is however very much impaired by man made emission in the protected band, leading to degraded measurements in several areas including parts of Europe and of China. However, many different international teams are now addressing cal val activities in various parts of the world, with notably large field campaigns either on the long time scale or over specific targets to address the specific issues. These campaigns take place in various parts of the world, in different environments from the Antarctic plateau to the deserts, from rain forests to deep oceans. Actually SMOS is a new sensor making new measurements paving the way to new applications. However it also requires a very fine analysis of the data so as to validate both the approach and the retrieval quality, as well as for monitoring the evolution of the sensor. To achieve such goals it is very important to link efficiently ground measurement to satellite measurements through field campaigns and related airborne acquisitions as well as with other existing sensors. This paper thus gives an overview of the science goals of the SMOS mission, a description of the main mission elements, and a foretaste of the first results including performances at brightness temperature as well as at geophysical parameters. It will include how the grond campaigns were elaborated to address the main cal Val activities accounting for SMOS specificities, in what context they were organized as well as the most significant results.

International audience; The CAROLS "Cooperative Airborne Radiometer for Ocean and Land Studies" L band radiometer was designed and built as a copy of the EMIRAD II radiometer constructed by the Technical University of Denmark team. It is a fully polarimetric and direct sampling correlation radiometer. CAROLS is installed on board a dedicated French ATR42 research aircraft, in conjunction with other airborne instruments. Following initial laboratory qualifications and other scientific campaigns, SMOS CAL/VAL campaigns involving 22 flights were carried out over South West France, the Valencia site and the Bay of Biscay (Atlantic Ocean) in spring 2010, in coordination with in situ field campaigns

In order to better understand the variability of surface CO2 in the Tropical Atlantic, a CARIOCA sensor has been installed on a PIRATA mooring at 6 degrees S, 10 degrees W in June 2006. The fugacity of CO2 (fCO(2)) is recorded hourly from 7 June 2006 to 30 October 2009 with two important data gaps. From July to September, an upwelling develops and a decrease in sea surface temperature (SST) is observed, associated with an fCO(2) increase. However, the highest fCO(2) is observed in October, after the upwelling season, due to the warming of surface waters. The region is a net source of CO2 to the atmosphere of 2.10 +/- 0.69 mol m-2 yr-1 in 2007. The monthly flux is maximum (3.21 +/- 0.8 mol m-2 yr-1) in November (averaged over 2006 and 2008). High frequency variability is observed throughout the time series but is particularly pronounced after the upwelling season. Biological and thermodynamic processes explain the diurnal variability. Dissolved inorganic carbon (DIC) is calculated from (alkalinity) TA and fCO(2) using an empirical TA-salinity relationship determined for the eastern equatorial Atlantic. Net community production (NCP) is calculated from DIC daily changes and ranges from 9 to 41 mmol m-2 d-1, which is consistent with previous measurements in this region.

Six cruises have been carried out in the eastern equatorial Atlantic between June 2005 and September 2007 to study the distribution of the surface total alkalinity (TA) and dissolved inorganic carbon (DIC). During these cruises a strong north-south gradient is observed in sea surface temperature (SST), sea surface salinity (SSS), DIC and TA. Low surface salinity waters are associated with low TA and low DIC. They are observed north of the equator (0 degrees-6 degrees N) in the Guinea current, whereas higher concentrations are observed south of the equator. TA-SSS and DIC-SST-SSS relationships are determined and are used to calculate surface fCO(2). Monthly maps of fCO2 are obtained, on a one degree grid, using SST and SSS fields for the region 10 degrees W-10 degrees E, 6 degrees N-10 degrees S from June to November. The monthly mean flux of CO2 ranges from 1.69 +/- 1.94 mmol m(2) day(-1) in November to 2.78 +/- 1.65 mmol m(-2) day(-1) in August over the region. Using the same gas exchange coefficient, the CO2 flux was calculated with the climatological AfCO(2). Our estimates show a stronger gradient between northern and southern waters than the climatology, probably due to a lack of data in the climatology as well as its 4 latitude by 5 longitude resolution.

International audience; Melatonin is a neurohormone that has been claimed to be involved in a wide range of physiological functions. Nevertheless, for most of its effects, the mechanism of action is not really known. In mammals, two melatonin receptors, MT 1 and MT 2 , have been cloned. They belong to the G-protein-coupled receptor (GPCR) superfamily. They share some specific short amino-acid sequences, which suggest that they represent a specific subfamily. Another receptor from the same subfamily, the melatonin-related receptor has been cloned in different species including humans. This orphan receptor also named GPR50 does not bind melatonin and its endogenous ligand is still unknown. Nevertheless, this receptor has been shown to behave as an antagonist of the MT 1 receptor, which opens new pharmacological perspectives for GPR50 despite the lack of endogenous or synthetic ligands. Moreover, MT 1 and MT 2 interact together through the formation of heterodimers at least in cells transfected with the cDNA of these two receptors. Lastly, signalling complexes associated with MT 1 and MT 2 receptors are starting to be deciphered. A third melatonin-binding site has been purified and characterized as the enzyme quinone reductase 2 (QR2). Inhibition of QR2 by melatonin may explain melatonin's protective effect that has been reported in different animal models and that is generally associated with its well-documented antioxidant properties.

International audience

Nine CARbon Interface OCean Atmosphere (CARIOCA) drifters were deployed in the Southern Ocean (south of the subtropical front, STF) between 2001 and 2006. They recorded 65 months of measurements in all seasons between 57°S and 40°S. Hydrological fronts detected by altimetry indicate that one buoy explored the polar zone (PZ) of the Atlantic Ocean and the western Indian Ocean; the remaining buoys explored the northern and southern parts of the subantarctic zone (SAZ) from the mid-Indian Ocean (73°E) to the eastern Pacific Ocean (112°W). The air-sea CO 2 fluxes along the buoy trajectories are primarily driven by the spatial variability of the fugacity of CO 2 in seawater, fCO 2 : in the SAZ, they vary between - 1.1 and -4.2 mol m -2 yr -1 , and the largest sinks occur close to the STF; in the PZ they vary between -1.6 and 0.6 mol m -2 yr-'. When spatially extrapolated over each region, the yearly fluxes amount to -0.8 Pg C yr -1 in the SAZ and to -0.1 Pg C yr -1 in the PZ, with very small seasonal variation. In winter-spring, the sea-surface salinity and sea-surface temperature indicate mixing with deep water close to the subantarctic front and an episodic signature of north Atlantic deep water close to the polar front (PF). These events are associated with fCO 2 close to equilibrium. On a small scale (of a few km), close to the STF, fCO 2 variations of 1-2 Pa (10-20 μatm) are associated with the presence of compensated mixed layers.

International audience; A novel abscisic acid (ABA)-deficient mutant, aba4, was identified in a screen for paclobutrazol-resistant germination. Compared with wild-type, the mutant showed reduced endogenous ABA levels in both dehydrated rosettes and seeds. Carotenoid composition analysis demonstrated that the defective locus affects neoxanthin synthesis. The ABA4 gene was identified by map-based cloning, and found to be a unique gene in the Arabidopsis genome. The predicted protein has four putative helical transmembrane domains and shows significant similarity to predicted proteins from tomato, rice and cyanobacteria. Constitutive expression of the ABA4 gene in Arabidopsis transgenic plants led to increased accumulation of trans-neoxanthin, indicating that the ABA4 protein has a direct role in neoxanthin synthesis. aba4 mutant phenotypes were mild compared with previously identified ABA-deficient mutants that exhibit vegetative tissue phenotypes. Indeed, ABA levels in seeds of aba4 mutants were higher than those of aba1 mutants. As aba1 mutants are also affected in a unique gene, this suggests that ABA can be produced in the aba4 mutant by an alternative pathway using violaxanthin as a substrate. It appears, therefore, that in Arabidopsis both violaxanthin and neoxanthin are in vivo substrates for 9-cis-epoxycarotenoid dioxygenases. Furthermore, significantly reduced levels of ABA were synthesized in the aba4 mutant on dehydration, demonstrating that ABA biosynthesis in response to stress must occur mainly via neoxanthin isomer precursors.

Ivabradine, a specific and use-dependent I(f) inhibitor, exerts anti-ischaemic activity purely by reducing heart rate. The aim of this work was to characterize its effect on the predominant HCN channel isoform expressed in human sino-atrial nodes (hSAN), to determine its kinetics in HCN channels from multicellular preparations and rate-dependency of its action.RT-PCR analysis of the four HCN channel isoforms was carried out on RNAs from hSAN. Patch-clamp and intracellular recordings were obtained from CHO cells stably expressing hHCN4 and isolated SAN, respectively. Beating rate of rat isolated atria was followed using a transducer.hHCN4 mRNAs were predominant in hSAN. Ivabradine induced a time-dependent inhibition of hHCN4 with an IC(50) of 0.5 microM. In rabbit SAN, ivabradine progressively reduced the frequency of action potentials: by 10% after 3 h at 0.1 microM, by 14% after 2 h at 0.3 microM and by 17% after 1.5 h at 1 microM. After 3h, ivabradine reduced the beating rate of rat right atria with an IC(30) of 0.2 microM. The onset of action of ivabradine was use-dependent rather than time-dependent with slower effects than caesium, an extracellular I (f) blocker. Ivabradine 3 microM decreased the frequency of action potentials in SAN from guinea-pig, rabbit and pig by 33%, 21% and 15% at 40 min, respectively.The use-dependent inhibition of hHCN4 current by ivabradine probably contributes to its slow developing effect in isolated SAN and right atria and to its increased effectiveness in species with rapid SAN activity.

International audience

Involves a growing disjuncture between processes of techonological development, application and diffusion and individual states, technological globalization contributes distinctively to regional security in East Asia. the potential contribution of technological globalization to sustainable economic development and prosperity are important to regional states due to their contribution to comprehensive security, and has rendered it less threatening in this region than elsewhere. east Asian states have supported the deepening of processes of technological globalization through enacting measures designed to facilitate the integration of local industries into transnational commercial networks on a regional or even global basis.

L'action des conservatoires régionaux se caractérise par l'usage pour la protection d'espèces ou d'espaces remarquables de la maîtrise foncière ou d'usage dans le cadre partenariale et consensuel. Les conservatoires régionaux sont des outils pertinents de

International audience

The Surface Ocean CO₂ Atlas (SOCAT), an activity of the international marine carbon research community, provides access to synthesis and gridded fCO₂ (fugacity of carbon dioxide) products for the surface oceans. Version 2 of SOCAT is an update of the previous release (version 1) with more data (increased from 6.3 million to 10.1 million surface water fCO₂ values) and extended data coverage (from 1968–2007 to 1968–2011). The quality control criteria, while identical in both versions, have been applied more strictly in version 2 than in version 1. The SOCAT website (http://www.socat.info/) has links to quality control comments, metadata, individual data set files, and synthesis and gridded data products. Interactive online tools allow visitors to explore the richness of the data. Applications of SOCAT include process studies, quantification of the ocean carbon sink and its spatial, seasonal, year-to-year and longerterm variation, as well as initialisation or validation of ocean carbon models and coupled climate-carbon models.

EUREC4A-OA is a large international project, connecting experts of ocean and atmosphere observations and modelling to enhance the understanding of key ocean and air-sea processes at the and to improve the skill of forecasts and future projections.The core of EUREC4A-OA has been a one-month (Jan/Feb 2020) field study in the western tropical North Atlantic Ocean where high-resolution, synchronized observational data have been collected using cutting-edge technology on ships, airplanes and autonomous vehicles. EUREC4A-OA investigates heat, momentum, water and CO2 transport within the ocean and exchanges across the air/sea interface using innovative high-resolution ocean observations and a hierarchy of numerical simulations. EUREC4A-OA focuses on ocean dynamics at the small-scale (0.1–100 km) and related atmospheric boundary layer processes. EUREC4A-OA is centered on the tropics where the primary external time scale affecting air-sea exchange is the diurnal cycle. However, the internal ocean and atmosphere dynamics convolute the diurnal, synoptic, seasonal and longer time scales to climate variability.The talk will present some of the results we obtained so far from the observations collected during the field experiment and from numerical simulations. The analyses carried out revealed with unprecedented detail the particular characteristics of the ocean small-scale dynamics, enlightening that such scales are also very active in the tropical regions and not only over the mid and higher latitudes ocean. Observations and models also unveil that the ocean small scales is important in contributing to the exchanges of heat, freshwater and CO2 between the ocean and the atmosphere. Moreover, the evaluation of the intensity of the coupling between the ocean and the atmosphere assessed from data and high-resolution simulations show that they are very important and intimately linked with the 3D structure of the small-scale ocean dynamics. The project has also provided preliminary results in terms of parametrization of different processes influencing the ocean and atmosphere exchanges that have been uncovered by the EUREC4A-OA field experiment. Notably a better representation of the small-scale freshwater patches due to precipitation has been introduced in the French Earth-System model that improves the overall simulations of air-sea interactions and clouds. A similar parametrization is now been introduced to take into account these physical processes in air-sea fluxes of CO2.