11 research outputs found
Gyroscopic Instability of a Drop Trapped Inside an Inclined Circular Hydraulic Jump
International audienceA drop of moderate size deposited inside a circular hydraulic jump remains trapped at the shock front and does not coalesce with the liquid flowing across the jump. For a small inclination of the plate on which the liquid is impacting, the drop does not always stay at the lowest position and oscillates around it with a sometimes large amplitude, and a frequency that slightly decreases with flow rate. We suggest that this striking behavior is linked to a gyroscopic instability in which the drop tries to keep constant its angular momentum while sliding along the jump
16p11.2 600 kb Duplications confer risk for typical and atypical Rolandic epilepsy
Rolandic epilepsy (RE) is the most common idiopathic focal childhood epilepsy. Its molecular basis is largely unknown and a complex genetic etiology is assumed in the majority of affected individuals. The present study tested whether six large recurrent copy number variants at 1q21, 15q11.2, 15q13.3, 16p11.2, 16p13.11 and 22q11.2 previously associated with neurodevelopmental disorders also increase risk of RE. Our association analyses revealed a significant excess of the 600 kb genomic duplication at the 16p11.2 locus (chr16: 29.5-30.1 Mb) in 393 unrelated patients with typical (n = 339) and atypical (ARE; n = 54) RE compared with the prevalence in 65 046 European population controls (5/393 cases versus 32/65 046 controls; Fisher's exact test P = 2.83 × 10−6, odds ratio = 26.2, 95% confidence interval: 7.9-68.2). In contrast, the 16p11.2 duplication was not detected in 1738 European epilepsy patients with either temporal lobe epilepsy (n = 330) and genetic generalized epilepsies (n = 1408), suggesting a selective enrichment of the 16p11.2 duplication in idiopathic focal childhood epilepsies (Fisher's exact test P = 2.1 × 10−4). In a subsequent screen among children carrying the 16p11.2 600 kb rearrangement we identified three patients with RE-spectrum epilepsies in 117 duplication carriers (2.6%) but none in 202 carriers of the reciprocal deletion. Our results suggest that the 16p11.2 duplication represents a significant genetic risk factor for typical and atypical R
Preoperative Vascular Imaging for Predicting Intraoperative Modification of Peripheral Arterial Cannulation during Minimally Invasive Mitral Valve Surgery
Objective Minimally invasive mitral valve surgery using peripheral cannulation for cardiopulmonary bypass (CBP) is increasingly prevalent. Although conceptually straightforward, peripheral CBP involves challenges and risks specific to this method of perfusion. The utility of preoperative vascular imaging in predicting these technical challenges and preventing vascular complications was studied. Methods We performed a retrospective analysis of 73 consecutive patients undergoing minimally invasive mitral valve surgery using femorofemoral CBP with intraluminal aortic occlusion balloon catheter. All patients underwent preoperative computed tomography angiogram or magnetic resonance angiography to study the iliofemoral axes. Results None of the patients operated with this technique was found to have arterial stenoses. Patients with a femoral artery diameter of less than 7.3 mm needed bilateral or side-graft arterial cannulation significantly more frequently than patients with larger femoral arteries (46.2% vs 9.1%, P = 0.001). There was a trend toward more frequent modification of arterial cannulation strategy in patients with body surface area less than 1.7 m2 compared with larger patients (body surface area, 1.7–2.0) (26.3% vs 8.3%, P = 0.07). Patients needing high CBP flow rate (>5 L/min) were no more likely to need dual arterial cannulation (18.2% vs 19.1%, P = 0.68). No patient experienced a vascular complication. Conclusions This preliminary study suggests that preoperative vascular imaging and patient evaluation may predict difficulties with femoral cannulation and perfusion, which can lead to better preoperative planning and potentially prevent vascular complications. Further data will be accumulated and analyzed to confirm these findings. </jats:sec
Perturbations on a liquid curtain near break-up: wakes and free-edges
International audienceWe report experiments on liquid curtains falling between two vertical wires. The flow is mainly driven by gravity, so that the Weber number (We) (ratio of momentum flux to twice the surface tension) is close to zero at the top of the curtain and increases downstream, with the possible existence of a location where We equals 1 (which turns out to be a singular point in the sheet, in terms of waves propagation). In the present paper, we focus on the curtain response to localized perturbations, i.e., formation of either surface waves or free edges behind a thin needle touching the curtain, with a special emphasis to what happens near the break-up limit. We extract and compare the shapes of two kind of “wakes” left behind the obstacle: classical triangular wake of standing sinuous waves and stationary hole involving two free edges pinned on the needle. It is found that these two wakes are very similar for high enough We, but behave very differently when We reaches 1 from above; the sinuous wake disappears, while the “hole wake” still exists, and its shape becomes rounded. Below We=1, the hole can either stay stable, oscillate or expand and break the curtain. We provide exact analytical expressions for stationary free-edges that compare very well with experiments
Économie des outre-mer français : une introduction
National audienceAlthough characterized by their geographic, demographic and institutional diversity, French overseas territories share common difficulties due to their size and their exposure to shocks, leading literature to focus on their economic vulnerabilities. These vulnerabilities are, first of all, inherited vulnerabilities resulting from structural factors in overseas economies, but also constructed vulnerabilities when they result from inappropriate political choices. This special issue devoted by the Revue and eacute;conomique to French overseas territories addresses both of these issues through seven contributions which, beyond identifying and evaluating the faced problems, strive to define possible solutions.Bien qu’ils se caractérisent par leur diversité géographique, démographique et institutionnelle, les territoires d’outre-mer français partagent, de par leur taille et leur exposition aux chocs, des difficultés qui poussent la littérature dédiée à se concentrer sur leurs vulnérabilités économiques. Il s’agit tout d’abord des vulnérabilités subies résultant des caractéristiques structurelles des économies ultramarines, mais également des vulnérabilités construites lorsqu’elles découlent de choix politiques inadaptés. Ce numéro spécial consacré par la Revue économique aux outre-mer français aborde l’une et l’autre de ces problématiques à travers sept contributions qui, au-delà d’identifier et d’évaluer les problèmes rencontrés, s’attachent à définir des pistes de solutions
Endovascular Vena Cavae Occlusion Technique in Minimally Invasive Tricuspid Valve Surgery in Patients With Previous Cardiac Surgery
Myocardial Protection in Minimally Invasive Mitral Valve Surgery: Retrograde Cardioplegia Alone Using Endovascular Coronary Sinus Catheter Compared With Combined Antegrade and Retrograde Cardioplegia
Final Primary Results from the Defifrance Registry Study: Effectiveness and Safety of Defibrotide in the Treatment of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome after Hematopoietic Cell Transplantation
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A personalized approach to guide allogeneic stem cell transplantation in younger adults with acute myeloid leukemia
International audienceA multistage model instructed by a large dataset (knowledge bank [KB] algorithm) has recently been developed to improve outcome predictions and tailor therapeutic decisions, including hematopoietic stem cell transplantation (HSCT) in acute myeloid leukemia (AML). We assessed the performance of the KB in guiding HSCT decisions in first complete remission (CR1) in 656 AML patients younger than 60 years from the ALFA-0702 trial (NCT00932412). KB predictions of overall survival (OS) were superior to those of European LeukemiaNet (ELN) 2017 risk stratification (C-index, 68.9 vs 63.0). Among patients reaching CR1, HSCT in CR1, as a time-dependent covariate, was detrimental in those with favorable ELN 2017 risk and those with negative NPM1 minimal residual disease (MRD; interaction tests, P = .01 and P = .02, respectively). Using KB simulations of survival at 5 years in a scenario without HSCT in CR1 (KB score), we identified, in a similar time-dependent analysis, a significant interaction between KB score and HSCT, with HSCT in CR1 being detrimental only in patients with a good prognosis based on KB simulations (KB score >= 40; interaction test, P = .01). We could finally integrate ELN 2017, NPM1 MRD, and KB scores to sort 545 CR1 patients into 278 (51.0%) HSCT candidates and 267 (49.0%) chemotherapy-only candidates. In both time-dependent and 6-month landmark analyses, HSCT significantly improved OS in HSCT candidates, whereas it significantly shortened OS in chemotherapy-only candidates. Integrating KB predictions with ELN 2017 and MRD may thus represent a promising approach to optimize HSCT timing in younger AML patients
