Search results for " Overview."
showing 10 items of 153 documents
Mapping Leisure across Borders
2013
Leisure has become an important domain in sociological research. While time is often spent in daily “pressing” activities, leisure time, in its multifaceted aspects, is rather oriented to convey new answers for individual and collective needs. Such answers are an important field for leisure studies as well as for the sociological questions connected with leisure. For instance, in developed countries, some of these answers concern the ways in which leisure may be spent in “the best way possible for me”, or “for my family”, or “for me with my friends”, hence focusing on it as a new basic human need/desire oriented to foster self-fulfillment. However, this idea of leisure as self-fulfillment m…
Pregnancy and periodontal disease: does exist a two-way relationship?
2017
Periodontal disease (PD) is an inflammatory disease of the tissues supporting the teeth. PD affects 65 million adults over the age of 30 years in the USA, and worldwide 5 to 70% of adults. Women who develop PD during pregnancy, itâs estimated 1 woman in 5, may have a higher risk of adverse pregnancy outcomes. PD during pregnancy starts by dental plaque and is increased by the action of pregnancy hormones. In order to study the effect of PD on adverse pregnancy outcomes, we have performed this narrative review summarising the current studies about the influence of PD on pregnancy. Periodontal pockets are a reservoir of oral microbiota. Modifications in oral microbiota may be considered as …
Historical Events in the Background of Hilbert’s Seventh Paris Problem
2015
David Hilbert’s lecture, “Mathematical Problems,” [Hilbert 1900] delivered in Paris in 1900 at the Second International Congress of Mathematicians, has long been recognized as marking a milestone in the history of mathematics. Certainly for Hilbert himself, this marked the single greatest event and a true turning point in his storied career. When historians and mathematicians have written about the so-called Hilbert problems, they have usually looked forward into the twentieth century, sometimes by viewing their resolution as markers for mathematical progress.
Lessons for mathematics higher education from 25 years of mathematics support
2018
International audience; The scale and scope of mathematics support within UK universities have grown significantly since the 1990s. Mathematics support has evolved from a ‘cottage industry' initiated by enthusiasts into a main-line student support provision overseen by institutional senior managers. Over this 25+ year period, the importance of the mathematical sciences in other disciplines has similarly boomed. No longer is it just engineering and physics undergraduates who need to acquire highly developed mathematical skills. Today geographers, bioscientists, sociologists and political scientists (to name but a few) have to be more skilled than ever before with understanding mathematical a…
The geometry of the secant caustic of a planar curve
2018
The secant caustic of a planar curve $M$ is the image of the singular set of the secant map of $M$. We analyse the geometrical properties of the secant caustic of a planar curve, i.e. the number of branches of the secant caustic, the parity of the number of cusps and the number of inflexion points in each branch of this set. In particular, we investigate in detail some of the geometrical properties of the secant caustic of a rosette, i.e. a smooth regular oriented closed curve with non-vanishing curvature.
The early historical roots of Lee-Yang theorem
2014
A deep and detailed historiographical analysis of a particular case study concerning the so-called Lee-Yang theorem of theoretical statistical mechanics of phase transitions, has emphasized what real historical roots underlie such a case study. To be precise, it turned out that some well-determined aspects of entire function theory have been at the primeval origins of this important formal result of statistical physics.
Normal forms and embeddings for power-log transseries
2016
First return maps in the neighborhood of hyperbolic polycycles have their asymptotic expansion as Dulac series, which are series with power-logarithm monomials. We extend the class of Dulac series to an algebra of power-logarithm transseries. Inside this new algebra, we provide formal normal forms of power-log transseries and a formal embedding theorem. The questions of classifications and of embeddings of germs into flows of vector fields are common problems in dynamical systems. Aside from that, our motivation for this work comes from fractal analysis of orbits of first return maps around hyperbolic polycycles. This is a joint work with Pavao Mardešić, Jean-Philippe Rolin and Vesna Župano…
Équidistribution non archimédienne et actions de groupes sur les arbres = Non-Archimedean equidistribution and group actions on trees
2016
We give equidistribution results of elements of function fields over finite fields, and of quadratic irrationals over these fields, in their completed local fields. We deduce these results from equidistribution theorems of common perpendiculars in quotients of trees by lattices in their automorphism groups, proved by using ergodic properties of the discrete geodesic flow. Nous donnons des résultats d'équidistribution d'éléments de corps de fonctions sur des corps finis, et d'irrationnels quadratiques sur ces corps, dans leurs corps locaux complétés. Nous déduisons ces résultats de théorèmes d'équidistribution de perpendiculaires communes dans des quotients d'arbres par des réseaux de leur g…
Théorème de Gabrielov et fonctions log-exp-algébriques
1997
Resume Nous obtenons le theoreme de Wilkie sur les fonctions log-exp-algebriques du theoreme du complementaire ≪ explicite ≫ de Gabrielov, et de notre presentation geometrique du theoreme de van den Dries, Macintyre et Marker sur les fonctions log-exp-analytiques.
Interaction Diagram of a Circular Bar in Torsion and Extension
1995
For a circular bar of perfectly plastic material and subjected to a cyclically variable torque and a constant axial force, the interaction (or generalized Bree) diagram is derived by a direct method in which Melan’s theorem is used to locate the nonratchetting load boundary.