10 research outputs found
Un nouveau taxon de la famille des Apocynaceae pour La Réunion : Leptadenia cf. madagascariensis Decne (Gentianales : Apocynaceae)
First report of Leptadenia madagascariensis Decne to La RĂ©union Island. The species is already known from other localities in the Southwest Indian Ocean area (at least Madagascar, the Comoro archipelago and Juan de Nova), where it is assumed native. The species name madagascariensis seems confused and might be considered as the African synonym of L. reticulata (Retz.) Wight & Arn., a species mostly cited from subtropical Asia. Finally, we propose to include the species under the name L. cf. madagascariensis in the Flora Index of Reunion Island as a cryptogenic species. In the meantime, we call for more in-depth studies to assess the true origin and ecological significance of the specie
Découverte d’un nouvel individu de Bois de senteur blanc, Ruizia cordata Cav. dans le Nord de l’île de La Réunion et bilan des connaissances sur l’état de conservation de l’espèce (Malvales, Malvaceae, Dombeyoideae)
Abstract : Ruizia cordata Cav., a native species of Réunion Island, is critically endangered as 4 individuals are known to be left in the wild at the dawn of 2015. Today, the success of ex situ programs initiated in the past 30 years is undeniable, ensuring available genetic strains conservation for the generations to come. The finding of a well-shaped new individual in February 2015 in the North coastal cliffs of the island has made a new genetic strain available for ex situ collections. As such, the perspective of discovering other natural individuals still stands as a hope for the long term conservation of R. cordata. Résumé : Ruizia cordata Cav. est en danger critique d’extinction, seulement 4 individus naturels connus et encore en vie sont répertoriés début 2015 à La Réunion. L'introductionex situde R. cordata reste un succès indiscutable, elle assure la conservation à long terme des souches génétiques actuelles. La découverte d’un nouvel individu mâle en bon état en février 2015 sur les falaises littorales du Nord de l’île apporte un espoir pour l’avenir du taxon, avec une nouvelle souche génétique à intégrer dans les efforts de multiplication et la perspective restaurée de trouver de nouvelles stations naturelles.Keywords : habitat lost, hybridisation, endemism, genetic isolation, insular ecosystems.Mots clés : perte d'habitat, hybridation, endémisme, isolation génétique, écosystèmes insulaires
Financing a sustainable ocean economy
The ocean, which regulates climate and supports vital ecosystem services, is crucial to our Earth system and livelihoods. Yet, it is threatened by anthropogenic pressures and climate change. A healthy ocean that supports a sustainable ocean economy requires adequate financing vehicles that generate, invest, align, and account for financial capital to achieve sustained ocean health and governance. However, the current finance gap is large; we identify key barriers to financing a sustainable ocean economy and suggest how to mitigate them, to incentivize the kind of public and private investments needed for topnotch science and management in support of a sustainable ocean economy
Nilpotent et diagonalisable, je t'aime moi non plus
On compare, dans , le cĂ´ne des matrices diagonalisables et
celui des matrices nilpotentes. On Ă©tudie les rapports de force (les
nilpotentes sont "négligeables" devant les diagonalisables), on dresse une
famille contre l'autre, puis on marie l'eau et le feu avec la décomposition de
Dunford et, comme dans toute saga, on est témoin de ruptures et de
retrouvailles (rapprochement des nilpotentes de rang maximal et des
diagonalisables Ă spectre simple)
Interaction with Artificial Companions: Presentation of an Exploratory Study
International audienceThe MoCA project aims to design and study children-companion relationship through virtual agents, personal robots and communicating devices. In this article, we present an exploratory study of the free 30min long interactions between children and a set of artificial, robot-like and virtual companions. We present a preliminary overview of the results obtained pending further analyses
A rapid and robust selection procedure for generating drug-selectable marker-free recombinant malaria parasites
International audienceExperimental genetics have been widely used to explore the biology of the malaria parasites. The rodent parasites Plasmodium berghei and less frequently P. yoelii are commonly utilised, as their complete life cycle can be reproduced in the laboratory and because they are genetically tractable via homologous recombination. However, due to the limited number of drug-selectable markers, multiple modifications of the parasite genome are difficult to achieve and require large numbers of mice. Here we describe a novel strategy that combines positive-negative drug selection and flow cytometry-assisted sorting of fluorescent parasites for the rapid generation of drug-selectable marker-free P. berghei and P. yoelii mutant parasites expressing a GFP or a GFP-luciferase cassette, using minimal numbers of mice. We further illustrate how this new strategy facilitates phenotypic analysis of genetically modified parasites by fluorescence and bioluminescence imaging of P. berghei mutants arrested during liver stage development
Accuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaign
International audienceThe Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September-October 2011 at Observatoire de Haute Provence (OHP). Two Raman lidars (IGN mobile lidar and OHP NDACC lidar), a stellar spectrometer (SOPHIE), a differential absorption spectrometer (SAOZ), a sun photometer (AERONET), 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow-White) participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these datasets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV) measurements. A novel method proposed by Bosser et al. (2010) is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4-5 %. Changes in calibration factor of IGN Raman lidar are evidenced which are attributed to frequent optical re-alignments. When modelling and correcting the changes as a linear function of time, the precision of the calibration factors improves to 2-3 %. However, the variations in the calibration factor, and hence the absolute accuracy, between methods and types of reference data remain at the level of 7 %. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow-White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (< 10 %RH) in the lower and middle troposphere reveals, on occasion, a lower RH detection limit in the Snow-White measurements compared to RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. On average, both RS92 and Snow-White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The IWV measurements from SOPHIE (night-time) and SAOZ (daytime) spectrometers, AERONET photometer (daytime) and calibrated Raman lidar (night-time) showed excellent agreement with the GPS IWV measurements
Figures de bibliothécaires
Cet ouvrage est le premier dictionnaire biographique consacré au monde des bibliothèques françaises. L’équipe scientifique réunie par Isabelle Antonutti a choisi 100 personnalités, femmes ou hommes, ayant exercé du milieu du XIXe à la fin du XXe siècle, à Paris ou en province. À travers elles, on retrouve toutes les évolutions du métier : pionniers de la lecture publique, bâtisseurs de l’université, savants du patrimoine, techniciens de la bibliothéconomie… Plus de 60 rédacteurs se sont associés à ce livre exceptionnel par son ambition comme par son projet : montrer qu’une bibliothèque est d’abord un projet social et humain