Search results for " Flux"
showing 10 items of 583 documents
Caractérisation expérimentale de la variabilité phénotypique du système racinaire nodulé de génotypes contrastés de pois (Pisum sativum L.), en phase…
2013
One of the challenges in plant breeding pea is to offer adapted genotypes to non-optimal environmental conditions. One of the factors limiting the agronomic performance of the pea is related to the environment plant sensitivity. Nodulated root system traits determine this sensitivity. The characterization of phenotypic traits combinations of the nodulated root system in different peas genotypes is interesting to suggest new plant breeding traits. The objective of this work was to experimentally characterize the phenotypic variability of the nodulated root system of 10 pea genotypes. The analysis was conducted under controlled conditions. The plants were grown in the absence of nitrates. Phe…
Observation of the suppression of the flux of cosmic rays above 4x10^19eV
2008
The energy spectrum of cosmic rays above 2.5 × 10¹⁸ eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index γ of the particle flux, J ∝ E-γ, at energies between 4 × 10¹⁸ eV and 4 × 10¹⁹ eV is 2.69 ± 0.02(stat) ± 0.06(syst), steepening to 4.2 ± 0.4(stat) ± 0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.
Zenith distribution and flux of atmospheric muons measured with the 5-line ANTARES detector
2010
The ANTARES high energy neutrino telescope is a three-dimensional array of about 900 photomultipliers distributed over 12 mooring lines installed in the Mediterranean Sea. Between February and November 2007 it acquired data in a 5-line configuration. The zenith angular distribution of the atmospheric muon flux and the associated depth-intensity relation are measured and compared with previous measurements and Monte Carlo expectations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is presented.
A numerical study of tropical cross-tropopause transport by convective overshoots
2007
Abstract. Observations obtained during the Tropical Convection, Cirrus and Nitrogen Oxides (TROCCINOX) golden day have revealed the presence of ice particles up to 410 K (18.2 km) 2 km above the local tropopause. The case was investigated using a three-dimensional quadruply nested non-hydrostatic simulation and Meteosat Second Generation (MSG) observations. The simulation reproduced the measurements along the flight track fairly well. A reasonable agreement with MSG observations was also achieved: the 10.8-μm brightness temperature (BT) minimum of 187 K was reproduced (a value 6 K colder than the environmental cold-point temperature) as was the positive BT difference between the 6.2- and 10…
Monitoring of mixed culture fermentations
2022
Current and future constraints linked to climate change and evolution of wine consumer demand are prompting the winemaking industry to consider adopting new practices to address the technical challenges resulting from this context. These challenges include the need to maintain a constant alcohol level despite increased sugar contents in the must, and to seek a wider diversity of aromatic profiles, while maintaining acceptable reproducibility.Fermentations with addition of non-Saccharomyces yeasts to the Saccharomyces cerevisiae species traditionally used to conduct alcoholic fermentation seem to be an interesting alternative to achieve these objectives. However, the numerous interactions be…
Etude et caractérisation de l'état " Viable mais Non Cultivable " chez Brettanomyces, une levure d'altération des vins : nouvel outil de détection et…
2011
The viable but not culturable (VBNC) state has been studied in detail in bacteria. It has been suggested that the VBNC state also exists in eukaryote cells, such as wine yeasts, including Brettanomyces in particular. We investigated the VBNC state in this yeast, focusing on the conditions for entry and exit, and the morphological and metabolic modifications associated with this state. We added sulfite (0.8 mg.L-1 molecular SO2) to induce the VBNC state. Increasing the pH of the medium inactivated the sulfite, allowing the cells to exit from the VBNC state and to become culturable again. In these conditions, we found that Brettanomyces VBNC cells were smaller than culturable cells, and that …
Study and characterization of the "Viable but non-culturable" state in Saccharomyces cerevisiae
2013
The viable but not culturable (VBNC) state has been studied in detail in bacteria. Bycontrast the VBNC state in other microorganisms, including particularly eukaryotes, has receivedmuch less attention. However, it has been suggested that in wine, Brettanomyces yeast cells mayenter a Viable But Not Culturable State, in particular in the presence of high, sulfur dioxide(SO2) concentration.To provide conclusive evidences for the existence of a VBNC state in yeast, especially in S.cerevisiae as a model organism, the capacity of different S cerevisiae strains to become viableand not cultivable after a sulfite stress with various concentrations of SO2 was studied by flowcytometry (FCM) using fluo…
Le système [i]agr[/i] de [i]Listeria monocytogenes[/i] et la croissance en biofilm : revisite des notions de communication, quorum sensing et auto-in…
2010
Communication orale, résumé; Parmi les mécanismes cellulaires qui participent à la mise en place des biofilms, l’échange de molécules de communication apparaît nécessaire chez de nombreux microorganismes. Listeria monocytogenes est une bactérie ubiquiste responsable de pathologies sévères chez des populations à risque (immunodéprimés, femmes enceintes, personnes âgées) en cas de consommation d’aliments contaminés. Nous avons récemment démontré que le système de communication agr est impliqué au cours de la croissance sessile de cette bactérie (Rieu et al., 2007). Par ailleurs, l’expression du système agr était hétérogène pendant la croissance en biofilm (Rieu et al., 2008) et localisée à sa…
Le système Agr de Listeria monocytogenes : revisite des notions de Quorum Sensing et auto-induction par cytométrie en flux
2011
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Recherche de critères phénotypiques et moléculaires discriminants des différentes espèces et sous-espèces du genre Pisum
2014
The Pisum genus presents a large genetic diversity, that makers difficult its taxonomic classification. The Center for Grain Legumes Genetic Resources holds 1800 pea accessions. Some of them are lacking passport data. Previous genotyping studies have identified SNP markers specific to wild Pisum pools. The main aim of my work was to conceive simple criteria in order to classify the unknown genotypes. Towards this goal, plants have been observed at the phenotypic level and their DNA were extracted for their characterisation using discriminating SNP markers. Furthermore, candidate genes of domestication were sequenced. Our results clearly showed distinctive traits between the P. sativum and P…