Search results for "sonde"

Examination of Escherichia coli from poultry for selected adhesin genes important in disease caused by mammalian pathogenic E. coli

2001

A collection of 1601 extraintestinal and intestinal Escherichia coli isolated from chickens, turkeys and ducks, in Belgium, France and Spain, was hybridised with gene probes specific for fimbrial and afimbrial adhesins (F17, F18, SSfa/F1C, Bfp, Afa, Cs31A, IntiminEae, Aida-1) of intestinal, urinary and invasive E. coli of mammals and with a probe specific for the P (Pap/Prs) fimbrial adhesin of urinary and invasive E. coli of mammals and birds. Three hundred and eighty-three strains (23.9%) were P-positive, 76 strains (4.8%) were Afa-positive, 75 strains (4.7%) were F17-positive, 67 strains (4.2%) were S-positive, 23 (1.4%) were Intimin-positive, and all were F18-, Cs31A-, Aida1- and Bfp-ne…

Intraseasonal wind anomalies related to wet and dry spells during the ?long? and ?short? rainy seasons in Kenya

1997

The largest part of Kenya exhibits two major rainy seasons, the March–May «long rains» and the October–December «short rains», both related to the passage of the ITCZ, but differing in the amount of rainfall recorded and its interannual variability. In order to investigate whether these differences also apply at intraseasonal time-scales, daily rainfall data for the peak month of each rainy season (April and November) were collected for 7 consecutive years (1982–1988). The network comprises 68 stations, from which a classification of the spatial patterns of daily rainfall anomalies has been performed. Wind anomalies corresponding to the various rainfall types and to specific regional rainfa…

Étude des propriétés optiques et spectroscopiques de nanorods dopés au lanthanide pour des applications de nanosondes en champ proche

2022

Lanthanide-doped nanoparticles constitute a versatile family of photoluminescent local nanoprobes. In this work, we study the photoluminescence of Eu3+-doped NaYF4 nanorods characterized by highly polarized spectra. We develop a full theoretical model and paraxial approximation for nanorod dipole emission. We measure the photoluminescence of individual nanorods by fluorescence confocal microscopy and determine some of their intrinsic optical properties. We also determine the nature (electric or magnetic) and orientations of dipoles moments of the optical transitions used for nanoprobing in the visible range.In addition to the full theoretical model and the paraxial approximation, Fourier mi…

Alignement moléculaire par impulsions laser ultrabrèves : Mesures & Applications

2009

The interaction of an intense ultrashort laser pulse with a molecular sample leads, after the end of the pulse, to molecular alignment at specific time under field-free conditions. This thesis is dedicated to the measurements and applications of this effect. The degree of alignment is determined through the variation of the refractive index induced by the rearrangement of the molecular dipoles. A two-dimensional technique allowing to measure molecular alignment on a single-shot basis is reported in this document. The alignment is then exploited in order to determine physical quantities which are usually difficult to estimate through others methods. The "cross-defocusing technique" has been …

Comparaison de deux méthodes de correction atmosphérique des données thermiques de Landsat TM

1996

The high resolution of Landsat Thematic Mapper (TM) thermal infrared data can be interesting in applications such as energy balance and crop water stress studies. However, surface temperature measurements are strongly affected by atmospheric effects, particularly by water vapour absorption, therefore a correction method is absolutely necessary. The impossibility of applying a split-window equation and the difficulty of having temporarily coincident radiosondes produce a slight use of Landsat TM data to obtain surface temperature. Vidal et al. show that in a zone with homogeneous climatic conditions, atmospheric correction can be evaluated by using energy balance equation and standard meteor…

Global equatorial variability of 850 and 200 hPa zonal winds from rawinsondes between 1963 and 1989

1995

The longitude-height-time variability of 3-month averaged zonal wind anomalies at 850 and 200 hPa over the equatorial area (5{degrees}N-5{degrees}S) is analyzed using a three-dimensional dataset constructed from rawinsonde data (1963-1989). The first mode, closely related to the Southern Oscillation Index, suggests a strong vertical coupling associated with a horizontal out-of-phase pattern between the central/western Pacific and the remainder of the equatorial belt. The vertical coupling appears to be phase-locked to the annual cycle with strongest intensities found over South America and near the maritime continent early in the calendar year and over the Pacific basin and Africa during th…

A case study on the formation and evolution of ice supersaturation in the vicinity of a warm conveyor belt\'s outflow region

2005

A case study is presented on the formation and evolution of an ice-supersaturated region (ISSR) that was detected by a radiosonde in NE Germany at 06:00 UTC 29 November 2000. The ISSR was situated in the vicinity of the outflow region of a warm conveyor belt associated with an intense event of cyclogenesis in the eastern North Atlantic. Using ECMWF analyses and trajectory calculations it is determined when the air parcels became supersaturated and later subsaturated again. In the case considered, the state of air parcel supersaturation can last for longer than 24h. The ISSR was unusually thick: while the mean vertical extension of ISSRs in NE Germany is about 500m, the one investigated here…

Populations bactériennes associées aux racines mycorhizées de Medicago truncatula: de la communauté à la souche bactérienne

2007

Une approche rapide pour le suivi de la colonisation mycorhizienne à arbuscules des plantes en agriculture

2001

National audience

Organisation de l'espaceur intergénique de l'ADN ribosomique nucléaire du Frêne commun (Fraxinus excelsior). Exploitation du polymorphisme moléculair…

1994

*INRA BP 86510 21065 Dijon cedex (FRA) Diffusion du document : INRA BP 86510 21065 Dijon cedex (FRA) Diplôme : Dr. d'Université