The data are assimilated by means of a reduced-order Kalman filter with a 3-D multivariate modal decomposition of the forecast error. It includes an adaptive-error estimate and a localization algorithm. A 3-D-Var scheme provides a correction for the slowly evolving large-scale biases in temperature and salinity. Altimeter data, satellite sea surface temperature and in situ temperature and salinity vertical profiles are jointly assimilated to estimate the initial conditions for numerical ocean forecasting. In addition to the quality control performed by data producers, the system carries out a proper quality control on temperature and salinity vertical profiles in order to minimise the risk of erroneous observed profiles being assimilated in the model. This paper describes the recent systems used by Mercator Océan and the validation procedure applied to current MyOcean systems as well as systems under development. The paper shows how refinements or adjustments to the system during the validation procedure affect its quality. Additionally, we show that quality checks (in situ, drifters) and data sources (satellite sea surface temperature) have as great an impact as the system design (model physics and assimilation parameters). The results of the scientific assessment are illustrated with diagnostics over the year 2010 mainly, assorted with time series over the 2007-2011 period. The validation procedure demonstrates the accuracy of MyOcean global products, whose quality is stable over time. All monitoring systems are close to altimetric observations with a forecast RMS difference of 7 cm. The update of the mean dynamic topography corrects local biases in the Indonesian Throughflow and in the western tropical Pacific. This improves also the subsurface currents at the Equator. The global systems give an accurate description of water masses almost everywhere. Between 0 and 500 m, departures from in situ observations rarely exceed 1 • C and 0.2 psu. The assimilation of an improved sea surface temperature product aims to better represent the sea ice concentration and the sea ice edge. The systems under development are still suffering from a drift which can only be detected by means of a 5-yr hindcast, preventing us from upgrading them in real time. This emphasizes the need to pursue research while building future systems for MyOcean2 forecasting.

[1] This work is dedicated to the study of the propagation of the Western Mediterranean Deep Water (WMDW) formed in the Gulf of Lions during the exceptional winter 2005. A simulation of the 1998-2008 period has been carried out with an eddy-resolving Ocean General Circulation Model of the Mediterranean Sea, driven by interannual high-resolution air-sea fluxes. This study first presents a validation of the recently improved model configuration against satellite observations. Then, we assess the ability of the model to reproduce the particularly intense deep convection event of winter 2005 in the Gulf of Lions. A huge volume of very dense water is formed in the simulation at that time (annual formation rate higher than 3 Sv). The thermohaline characteristics of the new WMDW allow a monitoring of its deep propagation. We identify several deep cyclones as mainly responsible of the fast spreading of the WMDW southwards in the Western Mediterranean. By comparing Eulerian and Lagrangian approaches, we estimate different transport times of the WMDW by these cyclonic eddies and compare them to those deduced from several observations. Finally, we argue that these cyclones favor the propagation of the WMDW thermohaline characteristics toward the Channel of Sardinia and decrease the volume of WMDW which can reach the Strait of Gibraltar.

No abstract

Stable gene transfer into hepatocytes might be used to compensate for a genetic deficiency affecting liver function or to deliver diffusible factors into the blood stream. In rats, we have combined retroviral-mediated gene transfer with a surgical procedure in which the liver is temporarily excluded from the circulation and infected in vivo. Partial hepatectomy was performed 24-48 hr before perfusion with virus to induce hepatocyte division and facilitate viral integration. A helper-free recombinant retrovirus coding for P-galactosidase with nuclear localization was used to score cells that expressed the transgene. For at least 3 months after gene transfer, up to 5% of hepatocytes expressed nuclear 3-galactosidase. Whereas in vitro reimplantation of genetically modified hepatocytes has proved to be inefficient in stably transferring genes into the liver, our approach provides a feasible alternative.A meethod for safe, efficient, and stable introduction of foreign DNA into hepatocytes would allow the development of protocols for the genetic treatment of many inborn errors of the metabolism.Replication-defective retroviral vectors ensure genomic integration of a few transgene copies in an unrearranged and permanent configuration transmitted to the cell progeny. The stability and long-term expression of transgenes introduced by retroviral vectors in vivo has been documented in a variety of somatic tissues (1-4). Use of helper-free packaging cell lines (5) has shown that the replication-defective recombinant retrovirus is not transmitted to nontargeted organs (4, 6) and a fortiori to other organisms.Freshly explanted hepatocytes are susceptible to retrovirus infection (7), and strategies for gene transfer into the liver involving in vitro infection of cultured liver cells followed by reimplantation have been proposed. However, whereas fresh hepatocytes can be efficiently engrafted into the spleen (8, 9) or the liver (10), most in vitro cultured and infected cells lose their capacity to be transplanted back (11). Therefore, the feasibility of large-scale gene transfer to the liver by this approach is unlikely. Our purpose was to develop an alternative method whereby the hepatocytes would directly receive the transgene in situ. Because cell division is required for genomic integration of retroviruses and because most hepatocytes are quiescent cells in the adult liver, retroviral infection of the steady-state organ is expected to be inefficient. On the other hand, partial resection of the liver is followed by a regenerative phase that rapidly reconstitutes a full-size organ. Many hepatocytes enter the cell cycle during this process (12, 13) and should be susceptible to retrovirus infection at this time. After complete restoration of the organ weight, hepatocytes return to a quiescent state (12, 13), and prolonged persistence of infected cells may be expected. Therefore, the in situ infection of hepatocytes with recombinant retroviral vectors may be a suitable method for long-term complementation of a genetic de...

Abstract. The French program Coriolis, as part of the French operational oceanographic system, produces the COriolis dataset for Re-Analysis (CORA) on a yearly basis. This dataset contains in-situ temperature and salinity profiles from different data types. The latest release CORA3 covers the period 1990 to 2010. Several tests have been developed to ensure a homogeneous quality control of the dataset and to meet the requirements of the physical ocean reanalysis activities (assimilation and validation). Improved tests include some simple tests based on comparison with climatology and a model background check based on a global ocean reanalysis. Visual quality control is performed on all suspicious temperature and salinity profiles identified by the tests, and quality flags are modified in the dataset if necessary. In addition, improved diagnostic tools have been developed -including global ocean indicators -which give information on the quality of the CORA3 dataset and its potential applications. CORA3 is available on request through the MyOcean Service Desk (http://www.myocean.eu/).