207 research outputs found

    Long-Range WindScanner System

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    The technical aspects of a multi-Doppler LiDAR instrument, the long-range WindScanner system, are presented accompanied by an overview of the results from several field campaigns. The long-range WindScanner system consists of three spatially-separated, scanning coherent Doppler LiDARs and a remote master computer that coordinates them. The LiDARs were carefully engineered to perform user-defined and time-controlled scanning trajectories. Their wireless coordination via the master computer allows achieving and maintaining the LiDARs' synchronization within ten milliseconds. The long-rangeWindScanner system measures the wind field by emitting and directing three laser beams to intersect, and then scanning the beam intersection over a region of interest. The long-range WindScanner system was developed to tackle the need for high-quality observations of wind fields on scales of modern wind turbine and wind farms. It has been in operation since 2013

    Comparison of 3D turbulence measurements using three staring wind lidars and a sonic anemometer

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    The goals are to compare lidar volume averaged wind measurement with point measurement reference sensors and to demonstrate the feasibility of performing 3D turbulence measurements with lidars. For that purpose three pulsed lidars were used in staring mode, placed so that their beams crossed close to a 3D sonic anemometer mounted at 78 m above the ground. The results show generally very good correlation between the lidar and the sonic times series, except that the variance of the velocity measured by the lidar is attenuated due to spatial filtering. The amount of attenuation can however be predicted theoretically by use of a spectral tensor model of the atmospheric surface-layer turbulence

    Associations of microvascular complications with all-cause death in patients with diabetes and COVID-19:the CORONADO, ABCD Covid-19 audit and AMERICADO study groups

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    AIM: To provide a detailled analysis of the microvascular burden in patients with diabetes hopitalized for COVD‐19. MATERIALS AND METHODS: We analysed data from the French CORONADO initiative and the UK Association of British Clinical Diabetologists (ABCD) COVID‐19 audit, two nationwide multicentre studies, and the AMERICADO, a multicentre study conducted in New York area. We assessed the association between risk of all‐cause death during hospital stay and the following microvascular complications in patients with diabetes hospitalized for COVID‐19: diabetic retinopathy and/or diabetic kidney disease and/or history of diabetic foot ulcer. RESULTS: Among 2951 CORONADO, 3387 ABCD COVID‐19 audit and 9327 AMERICADO participants, microvascular diabetic complications status was ascertained for 1314 (44.5%), 1809 (53.4%) and 7367 (79.0%) patients, respectively: 1010, 1059 and 1800, respectively, had ≄1 severe microvascular complication(s) and 304, 750 and 5567, respectively, were free of any complications. The patients with isolated diabetic kidney disease had an increased risk of all‐cause death during hospital stay: odds ratio [OR] 2.53 (95% confidence interval [CI] 1.66‐3.83), OR 1.24 (95% CI 1.00‐1.56) and OR 1.66 (95% CI 1.40‐1.95) in the CORONADO, the ABCD COVID‐19 national audit and the AMERICADO studies, respectively. After adjustment for age, sex, hypertension and cardiovascular disease (CVD), compared to those without microvascular complications, patients with microvascular complications had an increased risk of all‐cause death during hospital stay in the CORONADO, the ABCD COVID‐19 diabetes national audit and the AMERICADO studies: adjusted OR ((adj)OR) 2.57 (95% CI 1.69‐3.92), (adj)OR 1.22 (95% CI 1.00‐1.52) and (adj)OR 1.33 (95% CI 1.15‐1.53), respectively. In meta‐analysis of the three studies, compared to patients free of complications, those with microvascular complications had an unadjusted OR for all‐cause death during hospital stay of 2.05 (95% CI 1.42‐2.97), which decreased to 1.62 (95% CI 1.19‐2.119) after adjustment for age and sex, and to 1.50 (1.12‐2.02) after hypertension and CVD were further added to the model. CONCLUSION: Microvascular burden is associated with an increased risk of death in patients hospitalized for COVID‐19

    Universal changes in biomarkers of coagulation and inflammation occur in patients with severe sepsis, regardless of causative micro-organism [ISRCTN74215569]

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    INTRODUCTION: PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis) was a phase III, randomized, double blind, placebo controlled, multicenter trial conducted in patients with severe sepsis from 164 medical centers. Here we report data collected at study entry for 1690 patients and over the following 7 days for the 840 patients who received placebo (in addition to usual standard of care). METHODS: Nineteen biomarkers of coagulation activation, anticoagulation, fibrinolysis, endothelial injury, and inflammation were analyzed to determine the relationships between baseline values and their change over time, with 28-day survival, and type of infecting causative micro-organism. RESULTS: Levels of 13 of the 19 biomarkers at baseline correlated with Acute Physiology and Chronic Health Evaluation II scores, and nearly all patients exhibited coagulopathy, endothelial injury, and inflammation at baseline. At study entry, elevated D-dimer, thrombin–antithrombin complexes, IL-6, and prolonged prothrombin time were present in 99.7%, 95.5%, 98.5%, and 93.4% of patients, respectively. Markers of endothelial injury (soluble thrombomodulin) and deficient protein C, protein S, and antithrombin were apparent in 72%, 87.6%, 77.8%, and 81.7%, respectively. Impaired fibrinolysis (elevated plasminogen activator inhibitor-1) was observed in 44% of patients. During the first 7 days, increased prothrombin time (which is readily measurable in most clinical settings) was highly evident among patients who were not alive at 28 days. CONCLUSION: Abnormalities in biomarkers of inflammation and coagulation were related to disease severity and mortality outcome in patients with severe sepsis. Coagulopathy and inflammation were universal host responses to infection in patients with severe sepsis, which were similar across causative micro-organism groups

    Epinephrine Versus Norepinephrine for Cardiogenic Shock After Acute Myocardial Infarction

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    BACKGROUND Vasopressor agents could have certain specific effects in patients with cardiogenic shock (CS) after myocardial infarction, which may influence outcome. Although norepinephrine and epinephrine are currently the most commonly used agents, no randomized trial has compared their effects, and intervention data are lacking. OBJECTIVES The goal of this paper was to compare in a prospective, double-blind, multicenter, randomized study, the efficacy and safety of epinephrine and norepinephrine in patients with CS after acute myocardial infarction. METHODS The primary efficacy outcome was cardiac index evolution, and the primary safety outcome was the occurrence of refractory CS. Refractory CS was defined as CS with sustained hypotension, end-organ hypoperfusion and hyperlactatemia, and high inotrope and vasopressor doses. RESULTS Fifty-seven patients were randomized into 2 study arms, epinephrine and norepinephrine. For the primary efficacy endpoint, cardiac index evolution was similar between the 2 groups (p = 0.43) from baseline (H0) to H72. For the main safety endpoint, the observed higher incidence of refractory shock in the epinephrine group (10 of 27 [37%] vs. norepinephrine 2 of 30 [7%]; p = 0.008) led to early termination of the study. Heart rate increased significantly with epinephrine from H2 to H24 while remaining unchanged with norepinephrine (p <0.0001). Several metabolic changes were unfavorable to epinephrine compared with norepinephrine, including an increase in cardiac double product (p = 0.0002) and lactic acidosis from H2 to H24 (p <0.0001). CONCLUSIONS In patients with CS secondary to acute myocardial infarction, the use of epinephrine compared with norepinephrine was associated with similar effects on arterial pressure and cardiac index and a higher incidence of refractory shock. (Study Comparing the Efficacy and Tolerability of Epinephrine and Norepinephrine in Cardiogenic Shock [OptimaCC]; NCT01367743) (J AmColl Cardiol 2018; 72: 173-82) (C) 2018 by the American College of Cardiology Foundation.Peer reviewe
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