Search results for "Conti"
showing 10 items of 3486 documents
Toward an Understanding of the Molecular Mechanism of the Reaction between 1-Methylpyrrole and Dimethyl Acetylenedicarboxylate. An ab Initio Study
1998
The molecular mechanism for the reaction between 1-methylpyrrole and dimethyl acetylenedicarboxylate (DMAD) has been studied using ab initio methods. Two alternative reaction pathways have been considered, both of which correspond to stepwise processes with initial, rate-determining formation of a common zwitterionic intermediate. This intermediate is formed by nucleophilic attack of the pyrrole ring to the carbon−carbon triple bond of DMAD. Closure of this intermediate (pathway A) affords a [4 + 2] cycloadduct, whereas intramolecular proton transfer (pathway B) affords a Michael adduct. The much larger potential energy barrier of the second step in pathway B relative to pathway A is respon…
La formation continue contre le chômage, une vision économique réévaluée de l'investissement éducatif ?
1995
Article repris dans problèmes économiques, n° 2472, du 15 mai 1996, pp. 7-15, sous le titre "Les études supérieures assurent-elles une protection contre le chômage ? Une comparaison internationale"; International audience; Dans un contexte de croissance des études supérieures, différenciée selon les pays et les sexes, quelle protection celles-ci assurent-elles contre le chômage ? L'auteur présente une analyse détaillée de cette protection selon le sexe, l'âge ou l'étape dans la carrière, pour les pays de l'OCDE. Les résultats en sont parfois surprenants. Puis il propose des explications à ces variations. Il montre enfin comment la théorie du capital humain a dû être aménagée pour pouvoir re…
Branches of index-preserving solutions to systems of second order ODEs
2009
We investigate the existence of a continuum of index-preserving solutions to a Dirichlet problem associated with a parameter-dependent system of second order ordinary differential equations, developing a detailed analysis on the behaviour of the branches of nontrivial solutions. Our approach is based on the Rabinowitz global bifurcation Theorem combined with the notion of index and nullity of suitable linear boundary value problems. An application of the result to the study of branches of odd, periodic solutions for suitable systems of two linearly coupled pendulums of lenghts variables is also analyzed.
An eigenvalue Dirichlet problem involving the p-Laplacian with discontinuous nonlinearities
2005
AbstractA multiplicity result for an eigenvalue Dirichlet problem involving the p-Laplacian with discontinuous nonlinearities is obtained. The proof is based on a three critical points theorem for nondifferentiable functionals.
Regularity of renormalized solutions to nonlinear elliptic equations away from the support of measure data
2018
We prove boundedness and continuity for solutions to the Dirichlet problem for the equation $$ - {\rm{div}}(a(x,\nabla u)) = h(x,u) + \mu ,\;\;\;\;\;{\rm{in}}\;{\rm{\Omega }} \subset \mathbb{R}^{N},$$ where the left-hand side is a Leray-Lions operator from $$- {W}^{1,p}_0(\Omega)$$ into W−1,p′(Ω) with 1 < p < N, h(x,s) is a Caratheodory function which grows like ∣s∣p−1 and μ is a finite Radon measure. We prove that renormalized solutions, though not globally bounded, are Holder-continuous far from the support of μ.
Evolution Problems Associated to Linear Growth Functionals: The Dirichlet Problem
2003
Let Ω be a bounded set inIR N with Lipschitz continuous boundary ∂Ω. We are interested in the problem
Nonlinear Diffusion in Transparent Media
2021
Abstract We consider a prototypical nonlinear parabolic equation whose flux has three distinguished features: it is nonlinear with respect to both the unknown and its gradient, it is homogeneous, and it depends only on the direction of the gradient. For such equation, we obtain existence and uniqueness of entropy solutions to the Dirichlet problem, the homogeneous Neumann problem, and the Cauchy problem. Qualitative properties of solutions, such as finite speed of propagation and the occurrence of waiting-time phenomena, with sharp bounds, are shown. We also discuss the formation of jump discontinuities both at the boundary of the solutions’ support and in the bulk.
Riconfigurazioni identitarie nei contesti urbani degradati: discontinuità e riflessività
2019
Che rilevanza ha il contesto territoriale nei percorsi biografici dei residenti? Che significato assumono in un determinato territorio i turning point, le discontinuità, gli eventi imprevisti che si verificano nella vita degli individui? E ancora, perché soggetti che nascono e vivono in ambienti degradati economicamente e culturalmente riescono a cambiare il corso della propria vita che sembrerebbe ripetersi con modalità abituali per altri consociati (familiari o residenti) con esiti di degrado personale o marginalità sociale? Nell’articolo, attraverso i dati di una ricerca si svilupperà la relazione che intercorre tra discontinuità biografiche e riflessività che nei turning point influenza…
Qui suis-je
2020
The scarcity of research on French immersion teachers’ professional identity contrasts with the increasing popularity of French immersion programs in Canada and the concomitant need for French immersion teachers. This study explores the professional identity negotiation of four French immersion teachers in Alberta, Canada, with a focus on discontinuity. Semi-structured interviews conducted face-to-face with the participants were analysed using dialogic narrative analysis. The findings highlight how discontinuity is occasioned by a change in knowledge about the French immersion teaching as a profession, encountering classroom realities, shifting one’s values concerning second language learni…
Continuity and discontinuity in the semantics of the Latin preposition per: a cognitive hypothesis
2011
Abstract We propose a description of the semantic network of the Latin prepositional phrase per ‘through’ + Accusative in the early stage of this language. Drawing upon the insights of Cognitive Grammar, we analyze the role of the schematic import in the spread from basic to abstract meanings. Finally, we draw a map of the polysemous network of per, showing that the continuity of the different, but consistently linked, meanings does not necessarily imply the unidirectionality of the concrete-to-abstract shifts.