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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’.

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.

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.

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.

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.

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.

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.