Search results for "45"
showing 10 items of 1896 documents
Une histoire de la Nièvre pendant la Seconde Guerre mondiale
2015
International audience; ...
Le rôle déterminant de la presse dans la vie des expulsés allemands
2016
This article focuses on the identity of the German expellees after World War II through the study of one of their publications, the Grafschafter Bote. For this population who is spread geographically all over Germany, the newspapers published by numerous associations have contributed to the creation and the maintaining of a collective identity able to sustain its position in the new German state. These newspapers still exist today and contribute to the strengthening of a particular identity.
Stable motivic homotopy theory at infinity
2021
In this paper, we initiate a study of motivic homotopy theory at infinity. We use the six functor formalism to give an intrinsic definition of the stable motivic homotopy type at infinity of an algebraic variety. Our main computational tools include cdh-descent for normal crossing divisors, Euler classes, Gysin maps, and homotopy purity. Under $\ell$-adic realization, the motive at infinity recovers a formula for vanishing cycles due to Rapoport-Zink; similar results hold for Steenbrink's limiting Hodge structures and Wildeshaus' boundary motives. Under the topological Betti realization, the stable motivic homotopy type at infinity of an algebraic variety recovers the singular complex at in…
Nonlinear multipliers and applications
1985
International audience
Intermittency in the homopolar disk-dynamo
2006
We study a modified Bullard dynamo and show that this system is equivalent to a nonlinear oscillator subject to a multiplicative noise. The stability analysis of this oscillator is performed. Two bifurcations are identified, first towards an \lq\lq intermittent\rq\rq state where the absorbing (non-dynamo) state is no more stable but the most probable value of the amplitude of the oscillator is still zero and secondly towards a \lq\lq turbulent\rq\rq (dynamo) state where it is possible to define unambiguously a (non-zero) most probable value around which the amplitude of the oscillator fluctuates. The bifurcation diagram of this system exhibits three regions which are analytically characteri…
Optical properties of chlorine-and oxygen-related defects in SiO$_2$ glass and optical fibers
2018
International audience; Photoinduced processes involving chlorine molecules in synthetic silica were studied. Interstitial Cl$_2$ in SiO$_2$ are prevented from VIS/UV photolysis by cage effect. However, they react with oxygen interstitials yielding photosensitive ClClO molecules absorbing at 264nm.
Evaluation agroécologique de systèmes de culture en zone tropicale humide : Cas de la mise en valeur agricole d'une savane herbacée acide (Plaine des…
2013
Dans les régions tropicales humides, concilier intensification agricole et protection des ressources naturelles est un défi majeur et difficile à relever. Dans les savanes acides du nord-est laotien, des systèmes de culture de semis direct sur couverture végétale (SCV), basés sur les trois principes du non-labour, d’une couverture permanente du sol, et sur la pratique de rotations culturales diversifiées, sont proposés comme alternative technique à l’intensification agricole conventionnelle basée sur le labour. Si ces systèmes ont connu une diffusion importante et rapide dans les grandes agricultures mécanisées, leur diffusion reste néanmoins à ce jour limitée en contexte de petite agricult…
Effect of onion consumption by rats on hepatic drug-metabolizing enzymes
2001
Fruits and vegetables or their natural constituents which increase detoxication enzymes and/or reduce activating enzymes are considered as good candidates to prevent chemically-induced carcinogenesis. In this study, rats were fed a diet supplemented with 20% onion powder for 9 days. Several cytochrome P450 (CYP)s enzymes (CYP 1A, 2B, 2E1, 3A), which are involved in carcinogen activation, were determined by measuring their enzyme activities using specific substrates. In addition, phase II enzymes activities such as UDP-glucuronosyltransferase (UGT) and glutathione S-transferase (GST), involved in detoxication of carcinogens, were measured. Protein levels of CYPs and GST A1/A2, A3/A5, Ml, M2 …
Three cytochrome P450 genes are over-expressed in ryegrass (Lolium sp.) plants resistant to the ALS inhibitors iodosulfuron+mesosulfuron or pyroxsula…
2013
One of the most intense abiotic stresses encountered by arable weeds infesting agricultural fields is herbicide application. Non-target-site based resistance (NTSR), which belongs to the weed herbicide stress response pathways, is an adaptive response to herbicides. Stress response is driven by gene regulation. It follows that NTSR is endowed by differences in the expression of a set of genes between sensitive and resistant plants. We developed an accurate and reliable quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay to detect differences in gene expression in the major grass weed Lolium sp. using two ALS inhibitors (iodosulfuron+mesosulfuron and pyroxsulam). Res…
Modeling small‐scale cassava starch extraction. Simulation of the reduction of water consumption through a recycling process
2010
International audience; The purpose of this study was to model the extraction unit operation of the cassava starch manufacturing process and to propose a realistic recycling simulation in order to reduce the volumes of effluents. The model was developed from reactors which are commonly used for cassava starch extraction at a household scale in Vietnam. The reactors were tested using inflow starch as a marker at the beginning of the batch process. The experimental residence time distribution (RTDexp) was calculated by the outflow of the starch concentration. Using Matlab®, the RTDexp was compared to the theoretical residence time distribution (RTDth). The dynamic model obtained was built up …