Stochastic transport to quantify errors in geophysical fluid dynamic simulations

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171 Definitive pacemaker requirement after percutaneous Edwards Sapien aortic valve implantation: a rare complication

In 2009, more than 6000 patients have been treated with percutaneous aortic valve implantation using one of the two commercialized models of bioprothesis. The occurrence of complete atrioventricular block (AV-Block) requiring a pacemaker was described after implantation, particularly with the Corevalve (up to 25%).Purpose of the StudyTo evaluate the occurrence of conduction abnormalities and requirements for permanent pacing after Edwards Sapien aortic valve implantation.MethodsWe analyzed the standard 12-lead electrocardiograms (ECGs) of 55 consecutive Pts in whom an Edwards Sapien aortic valve was successfully implanted between June 2006 and December 2008 using either trans-femoral or trans-apical approach. We examined the ECGs before treatment, at day 1, and at one-month and analyzed the presence of a second or third-degree AV-block.ResultsMean age was 82 +/- 8.4 years and 46% were female. Logistic Euroscore was 27.8 + 14.9%. We noted a slight increase in HR at day-1 (78.8 + 16 vs 74.9 + 13 b / min, p=0.005) with decrease in QT interval (395±47.7 vs 416.8±40.2 ms, p=0.02). These values returned to baseline values at 1 month. There was no change in PR interval (198.8±42.4 vs 199.7±45.7 ms at day 1, p=0.98 and 199.3±39.8 ms at day 30, p=0.56) and QRS duration (113.3±26.2 vs 116.8±28 ms at day 1, p=0.14 and 113.2±25.4 ms at day 30, p=0.63) neither in the occurrence of hemiblocks. A new left bundle branch developed in 5 Pts (9%) at day one but was not present anymore at day-30. A permanent pacemaker was implanted in 2 cases (4.1%) for 3-degree AV-block: at day 3 one for persistent AV-Block developed immediately after aortic valve predilatation and at day 10 in the second case due to the delayed occurrence of 3-degree AV-Block.ConclusionsIn our experience, conductive disorders and the requirement of a definitive pacemaker after implantation of an Edwards-Sapien bioprothesis are unfrequent (4.1%)

Stochastic Reynolds theorem and generalized subgrid tensor

International audienceWe propose a representation that allows decomposing the flow velocity in terms of a smooth component and a highly oscillating random component. This decomposion leads through a stochastic representation of the Reynolds transport theorem to a large-scale expression of the Navier-Stokes equations. In this work we show the benefit of such a representation to construct low order dynamical systems that include naturally a dissipative term related to the action of the small-scale random component

Soil type and soil preparation influence vine development and grape composition through its impact on vine water and nitrogen status

The influence of soil type and preparation on vine development and grape composition was investigated in a 50 ha estate located in Saint-Emilion (Bordeaux, France) and planted predominantly with Merlot. Part of the vineyard was planted down the slopes and another part of the vineyard was planted on terraces, where soils were profoundly modified through soil preparation. Grape composition (berry weight, sugar, total acidity, malic acid and pH), vigor (pruning weight), vine nitrogen status (Yeast Available Nitrogen (YAN) in grapes) and vine water status (δ13C) was measured at a very high density grid of 10 data points per hectare. Water deficit was globally weak over the estate because of high soil water holding capacity whereas vine nitrogen status was highly variable. Vine vigor and grape composition were predominantly driven by vine nitrogen status. On terraces, where soils were deep, due to invasive soil preparation, water deficits were particularly small or non-existent and vine nitrogen status was highly variable. Grape quality potential was medium to low, except in places with low nitrogen status, but at the expense of low yields. On parcels planted down the slopes water deficits were recorded because vine rooting was limited by compact subsoils. Vine nitrogen status was homogeneous. Grape quality and yield were medium to high and relatively homogeneous. When possible, downhill plantations are to be preferred over terraces because in the latter vine yield and quality parameters are highly variable because of massive soil movements prior to plantation

Estratigrafia e evolução paleoambiental da Sequência Lenheiro, Mesoproterozoico, São João Del Rei, MG

A Sequência Lenheiro da Formação Tiradentes, Mesoproterozoico, registra depósitos de um sistema deltaico com influência de maré, progradante para SSE. Os afloramentos estendem-se por dezenas de quilômetros pelas serras de São José e do Lenheiro, a leste e oeste do município de São João del Rei, Minas Gerais. O presente trabalho elabora dois perfis estratigráficos em escala 1:20 na Sequência Lenheiro, totalizando 150 e 130 m cada. Foram reconhecidas e interpretadas 16 fácies sedimentares, agrupadas em sete associações de fácies. A partir do conjunto de associações e suas relações laterais observadas em campo, foi possível a interpretação de ambientes deposicionais. Na região do prodelta predominam depósitos de decantação de finos. Na frente deltaica, tornam-se mais frequentes arenitos com estruturas trativas e gravitacionais, e, em alguns deles, convoluções relacionadas a instabilidade tectônica ou de carga sedimentar. Na região da planície deltaica, é registrada a migração de barras de maré, representadas por arenitos com estratificação cruzada com recobrimento pelítico nos foresets, e, em direção ao continente, canais fluviais também com influência de marés. Nas porções mais continentais da sucessão ocorrem depósitos conglomeráticos, areníticos e pelíticos interpretados como canais e barras de um sistema fluvial entrelaçado com planície de inundação. O padrão grano e estratocrescente bem marcado nos perfis, o empilhamento vertical das associações de fácies e a relação lateral entre elas denotam um progressivo raseamento da sucessão. A Sequência Lenheiro, portanto, representa um delta de rio entrelaçado com influência de maré, com sentido de descarga fluvial para sul

Un domaine d’Henri Ier de Montmorency au temps d’Olivier de Serres : la Grange des Prés, à Pézenas

Devenu gouverneur du Languedoc, de Provence, du Dauphiné et de Guyenne en 1567, Henri Ier duc de Montmorency, seigneur de Damville, amiral et connétable de France (1524-1614), administra et contrôla durant 51 ans, de 1563 à 1614, les affaires du Languedoc dans ses limites de l’époque, au nom des rois de France qui se succédèrent. Comme son père Anne de Montmorency, il eut à faire face aux premières guerres de Religion qui opposèrent de manière souvent très violente catholiques et protestants. Il mena avec de grandes difficultés sa charge à partir de Pézenas, capitale des États du Languedoc. Imprégné des nouvelles idées et adhérant au protestantisme familial par conviction, il s’intéressa à l’architecture, à l’agronomie et à l’hydraulique. Il s’attacha à mettre en pratique les conseils d’Olivier de Serres, dans l’aménagement d’un grand domaine, situé sur les bords de l’Hérault, la Grange des Prés. Il acheta celui-ci en 1587 et y fit construire une nouvelle résidence prestigieuse. D’une surface de près de 150 ha, ce domaine comportait un « enclos » de 10 ha qu’il renforça par une enceinte afin de protéger un château à tourelles et d’importants communs desservis par trois grandes cours. Il fit aménager également des jardins d’agrément ornés de grottes et de fontaines, un vivier et un système hydraulique remarquables. Les travaux commencés en 1587 furent poursuivis jusqu’en 1611, soit quatre ans avant son décès. Contemporain d’Olivier de Serres (1539-1619), le duc de Montmorency s’inspira de son Traité d’agriculture et mesnage des Champs (1600) pour l’aménagement de ses terres. Il fut enfin, un admirateur du médecin et botaniste Pierre Richer de Belleval créateur, en 1593, du premier jardin botanique de France, le Jardin des Plantes de Montpellier. Monument historique depuis 2015, le domaine de la Grange des Prés demeure un des fleurons du patrimoine d’Occitanie et de l’héritage spirituel d’Olivier de Serres (1532-1619) dont on célèbre en 2019, le quatrième centenaire de sa mort.Having become governor of Languedoc, of Provence, of Dauphiné and Guyenne, Henry the 1st Duke of Montmorency, Lord of Damville, admiral and constable of France (1524-1614), administers and controlled the affairs of Languedoc as it was then, for 51 years from 1563 to 1614, in the name of the kings of France at the time. Like his father, he had to face the first Wars of Religion which violently opposed Catholics and Protestants. He fulfilled his very arduous task from his base in Pezenas, capital of the states of Languedoc. Inspired by current new ideas and following with conviction in the footsteps on his family’s Protestantism, he took a lively interest in architecture, agronomy and hydraulics. He put into practice the precepts of Olivier de Serres, in the development of the large estate of La Grange des Prés, situated on the banks of the Herault river. He bought it in 1587 and built a prestigious residence in the grounds. Converting an area of about 150 hectares, this estate included an enclosure of 10 hectares which he strengthened with a surrounding wall to protect a castle with towers and important outbuildings connected to three different courtyards. He also created leisure gardens with grottos and fountains, fish ponds and a remarkable hydraulic system. The works which started in 1587 continued until 1611, four years before his death. A contemporary of Olivier de Serres (1539-1619), the Duke of Montmorency took his inspiration from his Traité d’agriculture et mesnage des Champs (1600) for the development of his estate. Finally he was a keen admirer of the doctor and botanist Pierre Richer de Belleval, creator in 1593 of the first botanical garden in France, Jardin des Plantes of Montpellier. A historical monument since 2015, the estate of La Grange des Prés remains one of the jewels in the crown of Occitan heritage and an outstanding example of the spiritual legacy of Olivier de Serres (1532-1619) whose death 4 hundred years ago was commemorated in 2019

Two bites at a cherry,

Two bites at a cherry.--"For bravery on the field of battle."--The Chevalier de Resseguier.--Goliath.--My cousin the colonel.--A Christmas fantasy, with a moral.--Her dying words.Mode of access: Internet

Comment améliorer le rendement des éoliennes ?

International audienceNul ne peut désormais ignorer l'impact néfaste du numérique sur l'environnement ! Néanmoins, les sciences du numérique peuvent aussi contribuer à l'optimisation de la production de certaines énergies renouvelables. Explications avec le scientifique Valentin Resseguier, qui utilise la modélisation des fluides pour améliorer le rendement des éoliennes. [Pour en savoir plus voir l'article Interstices]</a

Large scale flows under location uncertainty: a consistent stochastic framework

International audienceUsing a classical example, the Lorenz-63 model, an original stochastic framework is applied to represent large-scale geophysical flow dynamics. Rigorously derived from a reformulated material derivative, the proposed framework encompasses several meaningful mechanisms to model geophysical flows. The slightly compressible setup , as treated in the Boussinesq approximation, brings up a stochastic transport equation for the density and other related thermo-dynamical variables. Coupled to the momentum equation through a forcing term, a resulting stochastic Lorenz-63 model is consistently derived. Based on such a reformulated model, the pertinence of this large-scale stochastic approach is demonstrated over classical eddy-viscosity based large-scale representations