On Freedom

This is an English translation of Emilie Du Châtelet's "Sur la liberté." This 18th century text discusses freedom of the will, determinism, and divine foreknowledge. Translated from French by Julia Jorati, with the help of Julie Roy. French edition of this text, on which this translation is based: “Sur la liberté,” in Oeuvres complètes de Voltaire, vol. 14, edited by William H. Barber, 484–502. Oxford: Voltaire Foundation, 1989

Mesure de la réfractivité atmosphérique par radar météorologique : comparaison avec un réseau de capteurs au sol.

International audienceLes radars météorologiques peuvent mesurer les changements de l'indice de réfraction de l'air dans les basses couches de l'atmosphère (Fabry et al., 1997, Fabry 2004). En utilisant les changements de phase provenant de cibles fixes aux alentours du radar, cette mesure permet d'obtenir une mesure de la réfractivité atmosphérique. Celle-ci dépend de la pression, la température et l'humidité. Les échos exploitables proviennent en général des cibles fixes telles que des châteaux d'eau, des tours ou des pylônes électriques. Pendant la campagne HyMeX (Hydrological cycle in Mediterranean expriment), cette mesure a été implémentée avec succès sur les radars bande S du réseau opérationnel de Météo-France. Afin de mieux comprendre les sources d'erreur autour de cette mesure, en particulier lorsque l'on monte en fréquence, Besson et al. 2012 a mené une simulation à partir des données de stations météorologiques automatiques. Cela a permis de mettre en avant une plus forte variabilité du signal l'été et en fin d'après-midi, quand la réfractivité est très sensible aux changements d'humidité. Cette simulation a ensuite été confirmée par des mesures radar. Est-il alors possible d'obtenir une information sur la turbulence à partir de cette mesure ? Pour échantillonner la variabilité spatiale et temporelle de la réfractivité, une analyse a été menée sur un an de données provenant du radar en bande C de Trappes, conjointement à une comparaison avec les stations automatiques alentours. L'étude présentée ici a permis de montrer qu'un lien qualitatif et quantitatif peut être établi entre les variabilités de la réfractivité mesurée par radar ou par les stations automatiques, qui sont liées à la turbulence atmosphérique de basses couches

BASTA : a 95GHz FM-­‐CW Cloud radar

International audienceGround-based continuous observation of non-precipitating clouds and fo

Use of multi-sources 10-years quantitative precipitation estimation re-analyses in a lumped rainfall-runoff model

International audienceL'objectif principal de ce projet est de produire une base de donnée de référence couvrant une période de 10 ans pour l'estimation quantitative de lames d'eaux précipitées (LEP). L'objectif est d'utiliser de façon optimale l'ensemble des informations disponibles (radars, pluviomètres horaires et journaliers, données atellite....) afin d'obtenir la meilleure estimation possible de la pluie précipitée. La base de données résultante sera une série de LPE horaire, de 1km2, associée a une estimation des incertitudes sur l'ensemble du territoire français. Cela sera une référence commune pour les hydrologues, permettant des applications telles que le calage des paramètres de modèles, l'evaluation de la valeur ajoutée d'une entrée spatio-temporelle haute résolution pour les modèles hydrologiques ect... / This project main objective is to produce a 10-year reference database of Quantitative Precipitation Estimations (QPE). The objective is to make use optimally at any time of all the available information (radars, hourly and daily rain gauges, satellite data, etc) to obtain the best possible surface precipitation estimation. The resulting data base, will consist of hourly, 1km² gridded QPE and associated estimation uncertainties over the entire French territory. This will represent a common reference for hydrologists useful for various applications such as the calibration of the hydrological model parameters, the assessment of the the added value of high space-time resolution input for hydrological models, etc

Effectiveness of Meningococcal B Vaccine against Endemic Hypervirulent Neisseria meningitidis W Strain, England

Serum samples from children immunized with a meningococcal serogroup B vaccine demonstrated potent serum bactericidal antibody activity against the hypervirulent Neisseria meningitidis serogroup W strain circulating in England. The recent introduction of this vaccine into the United Kingdom national immunization program should also help protect infants against this endemic strain

The chemical composition of a new “mica sandwich” foraminiferal species from the East Coast of Korea: Capsammina crassa sp. nov.

We describe a new agglutinated monothalamous foraminiferal species, Capsammina crassa sp. nov., based on integrated observations of the test morphology and the chemical characteristics of materials composing the test. The new species was found at a depth of <60 m on the East coast of Korea. The test morphology is typical of the genus Capsammina, comprising two or more mica plates with a ring of finely agglutinated mineral grains sandwiched between them and surrounding the cell body. There is no distinct test aperture. Elemental analyses of the agglutinated grains revealed 15 different types of mineral grains of which quartz is the most abundant. The surface areas of grains exposed on fractured surfaces ranged from 1.6 to 7,700 μm2 and the large plate-like grains forming the upper and lower surfaces measured about 420–2,350 μm in maximum width. The new species is morphologically similar to C. patelliformis, however, the differences in size, distribution area and depth support that these two species are distinct. This discovery is the first record of the genus Capsammina from the North Pacific. Therefore, it extends the biodiversity and geographical distribution of the genus Capsammina, which has been reported only from the bathyal NE Atlantic. Our finding also suggests the possibility of additional discovery of monothalamous foraminifera from around Korea

Agglutination of benthic foraminifera in relation to mesoscale bathymetric features in the abyssal NE Atlantic (Porcupine Abyssal Plain)

Abyssal hills, small topographic features rising above the abyssal seafloor (< 1000 m altitude), have distinct environmental characteristics compared to abyssal plains, notably the presence of coarser-grained sediments. As a result, they are a major source of habitat heterogeneity in the deep sea. The aim of this study was to investigate whether there is a link between abyssal hills and the test characteristics of selected agglutinated benthic foraminiferal species. We analysed 1) the overall morphometry, and 2) the granulometric and chemical (elemental) characteristics of the agglutinated tests of ten common foraminiferal species (Adercotryma glomerata, Ammobaculites agglutinans, Cribrostomoides subglobosus, Lagenammina sp.1, Nodulina dentaliniformis, Portatrochammina murrayi, three Reophax sp. and Recurvoides sp. 9) at four sites (two on top of abyssal hills and two on the adjacent plain) in the area of the Porcupine Abyssal Plain Sustained Observatory, northeast Atlantic. The foraminiferal test data were compared with the particle size distribution and elemental composition of sediments from the study sites in order to explore possible grain size and mineral selectivity. We found differences in the visual appearance of the tests (i.e. the degree of irregularity in their shape), which was confirmed by morphometric analyses, related to seafloor topography. The agglutinated foraminifera selected different sized particles on hills and plains, reflecting the distinct granulometric characteristics of these settings. These characteristics (incorporation of coarse particles, test morphometry) could provide evidence for the recognition of ancient abyssal hill environments, as well as other palaeoceanographic settings that were characterised by enhanced current flow. Furthermore, analyses of sediment samples from the hill and plain sites using wavelength dispersive X-ray fluorescence (WD-XRF) yielded different elemental profiles from the plains, probably a result of winnowing on the hills, although all samples were carbonate-rich. In contrast, the majority of the agglutinated tests were rich in silica, suggesting a preferential selection for quartz

The catastrophic flash-flood event of 8–9 September 2002 in the Gard region, France: a first case study for the Cévennes–Vivarais Mediterranean Hydrometeorological Observatory

The Cévennes–Vivarais Mediterranean Hydrometeorological Observatory (OHM-CV) is a research initiative aimed at improving the understanding and modeling of the Mediterranean intense rain events that frequently result in devastating flash floods in southern France. A primary objective is to bring together the skills of meteorologists and hydrologists, modelers and instrumentalists, researchers and practitioners, to cope with these rather unpredictable events. In line with previously published flash-flood monographs, the present paper aims at documenting the 8–9 September 2002 catastrophic event, which resulted in 24 casualties and an economic damage evaluated at 1.2 billion euros (i.e., about 1 billion U.S. dollars) in the Gard region, France. A description of the synoptic meteorological situation is first given and shows that no particular precursor indicated the imminence of such an extreme event. Then, radar and rain gauge analyses are used to assess the magnitude of the rain event, which was particularly remarkable for its spatial extent with rain amounts greater than 200 mm in 24 h over 5500 km2. The maximum values of 600–700 mm observed locally are among the highest daily records in the region. The preliminary results of the postevent hydrological investigation show that the hydrologic response of the upstream watersheds of the Gard and Vidourle Rivers is consistent with the marked space–time structure of the rain event. It is noteworthy that peak specific discharges were very high over most of the affected areas (5–10 m3 s−1 km−2) and reached locally extraordinary values of more than 20 m3 s−1 km−2. A preliminary analysis indicates contrasting hydrological behaviors that seem to be related to geomorphological factors, notably the influence of karst in part of the region. An overview of the ongoing meteorological and hydrological research projects devoted to this case study within the OHM-CV is finally presented