30 research outputs found
Introduction to the French GEOTRACES North Atlantic Transect (GA01): GEOVIDE cruise
The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June 2014. In this special issue (https://www.biogeosciences.net/special_issue900.html), results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 18 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue
Single-stage revascularization and free flap coverage in the treatment of ischemic lower limb lesions.
Evidence of high N2 fixation rates in the temperate northeast Atlantic
Diazotrophic activity and primary production (PP) were investigated along two transects (Belgica BG2014/14 and GEOVIDE cruises) off the western Iberian Margin and the Bay of Biscay in May 2014. Substantial N2 fixation activity was observed at 8 of the 10 stations sampled, ranging overall from 81 to 384â”molâNâmâ2âdâ1 (0.7 to 8.2ânmolâNâLâ1âdâ1), with two sites close to the Iberian Margin situated between 38.8 and 40.7ââN yielding rates reaching up to 1355 and 1533â”molâNâmâ2âdâ1. Primary production was relatively lower along the Iberian Margin, with rates ranging from 33 to 59âmmolâCâmâ2âdâ1, while it increased towards the northwest away from the peninsula, reaching as high as 135âmmolâCâmâ2âdâ1. In agreement with the area-averaged Chl a satellite data contemporaneous with our study period, our results revealed that post-bloom conditions prevailed at most sites, while at the northwesternmost station the bloom was still ongoing. When converted to carbon uptake using Redfield stoichiometry, N2 fixation could support 1â% to 3â% of daily PP in the euphotic layer at most sites, except at the two most active sites where this contribution to daily PP could reach up to 25â%. At the two sites where N2 fixation activity was the highest, the prymnesiophyteâsymbiont Candidatus Atelocyanobacterium thalassa (UCYN-A) dominated the nifH sequence pool, while the remaining recovered sequences belonged to non-cyanobacterial phylotypes. At all the other sites, however, the recovered nifH sequences were exclusively assigned phylogenetically to non-cyanobacterial phylotypes. The intense N2 fixation activities recorded at the time of our study were likely promoted by the availability of phytoplankton-derived organic matter produced during the spring bloom, as evidenced by the significant surface particulate organic carbon concentrations. Also, the presence of excess phosphorus signature in surface waters seemed to contribute to sustaining N2 fixation, particularly at the sites with extreme activities. These results provide a mechanistic understanding of the unexpectedly high N2 fixation in productive waters of the temperate North Atlantic and highlight the importance of N2 fixation for future assessment of the global N inventory.ISSN:1726-4170ISSN:1726-417
Adipose-derived stromal vascular fraction aids epithelialisation and angiogenesis in an animal model
ACA technique: stromal vascular fraction, platelet-rich plasma and microfat for autologous regeneration and skin rejuvenation
Introduction to the French GEOTRACES North Atlantic Transect (GA01): GEOVIDE cruise
The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June 2014. In this Special Issue, results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among seventeen articles. Here, the scientific context, project objectives and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue