15 research outputs found

    Mesoscale distribution patterns of diatoms in surface sediments as tracers of coastal upwelling of the Galician shelf (NW Iberian Peninsula)

    Get PDF
    Diatom distribution on continental shelf sediments from the upwelling area off Galicia (NW Iberian Peninsula) has been determined in 78 surface sediment samples. Three well defined biofacies with a close relationship to upwelling influence along the coast have been distinguished from both the absolute diatom abundances in the sediments and assemblage diatom composition based on multivariate statistics: Rias Baixas and the shelf areas south and north to Cape Finisterre. Chaetoceros resting spores as well as highest absolute diatom content in the sediments are recorded in the highly productive Rias Baixas where most of the primary production is due to intense upwelling phenomena. The western shelf, south of Cape Finisterre. is characterized by Thalassionema nitzschioides and Thalassiosira cf. leptopus. Both taxa reflect a minor influence of upwelling conditions and productivity related to more persistent nutrient input due to coastal outwelling rather than upwelling. Minor and patchy upwelling conditions as well as lower productivity in the northern shelf are characterized by the lowest absolute diatom content in the sediments and the important increase in relative abundance of the resistant Paralia sulcata. Caution must be taken in the interpretation of Paralia sulcata dominated biofacies in downcore studies since a juxtaposition of discontinuous upwelling conditions and dissolution effects may be the factors responsible for the relative increase on the taxon in the sediments. The obtained results show the extent and limitations of fossil diatom distribution in surface sediments as tracers of regional coastal upwelling conditions in continental shelves where the existence of extensive areas of relict sediments and transported diatoms may mask the present-day upwelling signal of the photic zone.This work was supported by the European Union in the framework of the MAST programme, contract no. MAS2-CT93-0069 (Ocean Margin Exchange, OMEX). It is also a contribution to projects XUGA10307B93 (Xunta de Guliciu) and APC-950010 (Direccibn General de Znvestigacibn Cien tljica y Ticnica)Peer reviewe

    The fingerprint of the summer 2018 drought in Europe on ground-based atmospheric CO2 measurements

    Get PDF
    During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018.The UK sites were funded by the UK Department of Business, Energy and Industrial Strategy (formerly the Department of Energy and Climate Change) through contracts TRN1028/06/2015 and TRN1537/06/2018. The stations at the ClimaDat Network in Spain have received funding from the ‘la Caixa’ Foundation, under agreement 2010-002624

    Zielgerichtete Volumentherapie durch Optimierung von Schlagvolumen (variation) bei Hochrisikoeingriffen:eine randomisierte kontrollierte Multicenter Pilotstudie

    No full text
    Subject: Perioperative hemodynamic optimization reduces the incidence of postoperative complications in patients after high-risk interventions. We investigated the influence of a targeted, individualized intraoperative volume therapy, based on measurements of stroke volume variation (SVV) and stroke volume (SV), on the postoperative patient outcome. Material, Methods: 52 high-risk patients (ASA 3 or 4) were treated with the consent of the respective ethics committee randomized either to a control group (group K, n = 26) or a targeted therapy group (group T, n = 26). Patients with cardiac arrhythmias or a tidal volume <7 ml / kg under mechanical ventilation were excluded. SVV and SV were measured continuously (FloTrac / Vigileo, Edwards Lifesciences, Irvine, USA). Patients of the therapie group received colloidal fluid (200 ml 6% HAES130 / 0.4) until a plateau is reached on the Frank-Starling curve (SVV <10% and SV increase <10% after volume release). On the intensive care unit organ dysfunction (SOFA score) and therapy intensity (TISS score) detected. Patients were postoperative over a period of 28 days is observed. Results: Both groups were similar in terms of ASA status, comorbidity, type and duration of the procedure (275 vs. 280 min), heart rate, blood pressure, and CVP to OP start. However, patients in group T were younger than in group K (68 vs. 73 years, p <0.05). Intraoperatively, patients of the therapy group received more colloids (1589 vs. 927 ml, p <0.05) and the SVV decreased significantly in the therapy group (from 9.0 to 8.0%, p <0.05), but not in the control group. The number of postoperative wound infections was also significantly lower in the therapy group (0 vs. 7, p <0.01). In addition, the proportion of patients with at least one complication (46 vs. 62%), the number of postoperative complications per patient (0.65 vs. 1.40), the maximum SOFA score (5.9 vs. 7,2) and the cumulative TISS score (69 vs. 83) were also lower in the therapy group. Conclusions: This pilot study suggests that targeted intraoperative volume therapy reduces the incidence of postoperative wound infections and organdy functions and thus the consumption of resources. this is the first multicenter study, which shows a positive effect on patient outcome by the perioperative use of extended hemodynamic monitoring. Courtesy of Edwards Lifesciences, Irvine, USA

    Goal-directed intraoperative fluid therapy guided by stroke volume and its variation in high-risk surgical patients:a prospective randomized multicentre study

    No full text
    <p>Perioperative hemodynamic optimisation improves postoperative outcome for patients undergoing high-risk surgery (HRS). In this prospective randomized multicentre study we studied the effects of an individualized, goal-directed fluid management based on continuous stroke volume variation (SVV) and stroke volume (SV) monitoring on postoperative outcomes. 64 patients undergoing HRS were randomized either to a control group (CON, n = 32) or a goal-directed group (GDT, n = 32). In GDT, SVV and SV were continuously monitored (FloTrac/Vigileo) and patients were brought to and maintained on the plateau of the Frank-Starling curve (SVV <10 % and SV increase <10 % in response to fluid loading). Organ dysfunction was assessed using the SOFA score and resource utilization using the TISS score. Patients were followed up to 28 days for postoperative complications. Main outcome measures were the number of complications (infectious, cardiac, respiratory, renal, hematologic and abdominal post-operative complications), maximum SOFA score and cumulative TISS score during ICU stay, duration of mechanical ventilation, length of ICU stay, and time until fit for discharge. 12 patients had to be excluded from final analysis (6 in each group). During surgery, GDT received more colloids than CON (1,589 vs. 927 ml, P <0.05) and SVV decreased in GDT (from 9.0 to 8.0 %, P <0.05) but not in CON. The number of postoperative wound infections was lower in GDT (0 vs. 7, P <0.01). Although not statistically significant, the proportion of patients with at least one complication (46 vs. 62 %), the number of postoperative complications per patient (0.65 vs. 1.40), the maximum sofa score (5.9 vs. 7.2), and the cumulative TISS score (69 vs. 83) tended to be lower. This multicentre study shows that fluid management based on a SVV and SV optimisation protocol is feasible and decreases postoperative wound infections. Our findings also suggest that a goal-directed strategy might decrease postoperative organ dysfunction.</p>

    Less invasive hemodynamic monitoring in critically ill patients

    No full text
    Over the last decade, the way to monitor hemodynamics at the bedside has evolved considerably in the intensive care unit as well as in the operating room. The most important evolution has been the declining use of the pulmonary artery catheter along with the growing use of echocardiography and of continuous, real-time, minimally or totally non-invasive hemodynamic monitoring techniques. This article, which is the result of an agreement between authors belonging to the Cardiovascular Dynamics Section of the European Society of Intensive Care Medicine, discusses the advantages and limits of using such techniques with an emphasis on their respective place in the hemodynamic management of critically ill patients with hemodynamic instability

    The fingerprint of the summer 2018 drought in Europe on ground-based atmospheric CO2 measurements

    No full text
    During the summer of 2018 a widespread drought developed over Northern and Central Europe. The significant increase in temperature and the reduction of soil moisture have influenced the carbon dioxide (CO2 ) exchanges between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in auto- and heterotrophic respiration, or allowing more frequent and/or stronger fires, which were particularly important in Sweden at the end of July 2018. In this study we characterise the resulting perturbation of the atmospheric CO2 seasonal cycles. The year 2018 has an excellent coverage of the European regions affected by drought, allowing to investigate how large-scale ecosystem flux anomalies impacted spatial CO2 gradients between stations in 2018. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the dense Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here we show that the usual summer minimum in CO2 mole fraction due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in northern Europe. Notwithstanding,the CO2 transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO2 uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration legated from the previous summer. For stations with sufficiently long time series, the amplitudes of the CO2 anomaly observed in 2018 were compared to previous European droughts in 2003 and 2015. Considering the areas most affected by the temperature anomalies during these years, we found a higher CO2 anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018.JRC.C.5-Air and Climat

    The fingerprint of the summer 2018 drought in Europe on ground-based atmospheric CO 2 measurements

    Get PDF
    International audienceDuring the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing theinvestigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS)network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here, we show that the usualsummer minimum in CO2 due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in Northern Europe. Notwithstanding, the CO2 transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO2 uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration inherited from the previous months due to the drought. For stations with sufficiently long time series, the CO2 anomaly observed in 2018 was compared to previous European droughts in 2003 and 2015. Considering the areas mostaffected by the temperature anomalies, we found a higher CO2 anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018.This article is part of the theme issue ‘Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale’
    corecore