Le devenir de la première union commencée hors mariage : une analyse comparative entre la France, l’Italie, la Suède et la Suisse à partir des enquêtes FFS des années 1990

Aujourd’hui, de plus en plus de couples commencent, en Europe, une première expérience conjugale hors mariage. Le devenir de ces unions fait l’objet de diverses questions : sont-elles plus fragiles que l’union maritale ? Sont-elles des épisodes de vie de couple temporaires ? Aboutissent-elles au mariage ? Sont-elles une nouvelle forme d’union parallèle à l’institution du mariage ? Existe‑t‑il différentes formes de cohabitation hors mariage selon les pays ? Enfin, quelle est la part de l’environnement familial et social dans le devenir de l’union ? Cet article se propose d’apporter des éléments de réponses à ces questions en utilisant les données recueillies au cours des années 1990 par les enquêtes Fécondité et famille, en France, en Italie, en Suède et en Suisse, pays représentatifs de la variété des situations conjugales et fécondes en Europe occidentale. Les méthodes d’analyses des biographies ont été retenues pour prendre en compte les durées écoulées et les caractéristiques individuelles et contextuelles.Today, in Europe, more and more couples are entering into a first conjugal experience outside marriage. Various questions are being raised about the evolution of these unions. Are they more precarious than marital unions? Are they temporary episodes of conjugal life? Do they lead to marriage? Are they a new, parallel form of union outside marriage? Are there different forms of cohabitation outside marriage in different countries? And finally, what role do the family context and social environment play in the evolution of the union? This article tries to answer some of these questions based on data gathered in the 1990s by Fertility and Family Surveys (FFS) conducted in France, Italy, Sweden and Switzerland, countries that represent the variety of conjugal and fertility situations in western Europe. Life history analysis methods were used to investigate the time intervals and individual and contextual characteristics involved

Use of Lagrangian simulations to hindcast the geographical position of propagule release zones in a Mediterranean coastal fish

The study of organism dispersal is fundamental for elucidating patterns of connectivity between populations, thus crucial for the design of effective protection and management strategies. This is especially challenging in the case of coastal fish, for which information on egg release zones (i.e. spawning grounds) is often lacking. Here we assessed the putative location of egg release zones of the saddled sea bream (Oblada melanura) along the south-eastern coast of Spain in 2013. To this aim, we hindcasted propagule (egg and larva) dispersal using Lagrangian simulations, fed with species-specific information on early life history traits (ELTs), with two approaches: 1) back-tracking and 2) comparing settler distribution obtained from simulations to the analogous distribution resulting from otolith chemical analysis. Simulations were also used to assess which factors contributed the most to dispersal distances. Back-tracking simulations indicated that both the northern sector of the Murcia region and some traits of the North-African coast were hydrodynamically suitable to generate and drive the supply of larvae recorded along the coast of Murcia in 2013. With the second approach, based on the correlation between simulation outputs and field results (otolith chemical analysis), we found that the oceanographic characteristics of the study area could have determined the pattern of settler distribution recorded with otolith analysis in 2013 and inferred the geographical position of main O. melanura spawning grounds along the coast. Dispersal distance was found to be significantly affected by the geographical position of propagule release zones. The combination of methods used was the first attempt to assess the geographical position of propagule release zones in the Mediterranean Sea for O. melanura, and can represent a valuable approach for elucidating dispersal and connectivity patterns in other coastal species

Pupil stabilization for SPHERE's extreme AO and high performance coronagraph system

We propose a new concept of pupil motion sensor for astronomical adaptive optics systems and present experimental results obtained during the first laboratory validation of this concept. Pupil motion is an important issue in the case of extreme adaptive optics, high contrast systems, such as the proposed Planet Finder instruments for the ESO and Gemini 8-meter telescopes. Such high contrast imaging instruments will definitively require pupil stabilization to minimize the effect of quasi-static aberrations. The concept for pupil stabilization we propose uses the flux information from the AO system wave-front sensor to drive in closed loop a pupil tip-tilt mirror located in a focal plane. A laboratory experiment validates this concept and demonstrates its interest for high contrast imaging instrument.Comment: This paper was published in Optics Express and is made available as an electronic reprint with the permission of OSA. The paper can be found at http://www.opticsexpress.org/abstract.cfm?id=144687 on the OSA websit

Spatial genetic structure in the saddled sea bream (Oblada melanura [Linnaeus, 1758]) suggests multi-scaled patterns of connectivity between protected and unprotected areas in the Western Mediterranean Sea

Marine protected areas (MPAs) and networks of MPAs are advocated worldwide for the achievement of marine conservation objectives. Although the knowledge about population connectivity is considered fundamental for the optimal design of MPAs and networks, the amount of information available for the Mediterranean Sea is currently scarce. We investigated the genetic structure of the saddled sea bream ( Oblada melanura) and the level of genetic connectivity between protected and unprotected locations, using a set of 11 microsatellite loci. Spatial patterns of population differentiation were assessed locally (50-100 km) and regionally (500-1000 km), considering three MPAs of the Western Mediterranean Sea. All values of genetic differentiation between locations (Fst and Jost's D) were non-significant after Bonferroni correction, indicating that, at a relatively small spatial scale, protected locations were in general well connected with non-protected ones. On the other hand, at the regional scale, discriminant analysis of principal components revealed the presence of a subtle pattern of genetic heterogeneity that reflects the geography and the main oceanographic features (currents and barriers) of the study area. This genetic pattern could be a consequence of different processes acting at different spatial and temporal scales among which the presence of admixed populations, large population sizes and species dispersal capacity, could play a major role. These outcomes can have important implications for the conservation biology and fishery management of the saddled sea bream and provide useful information for genetic population studies of other coastal fishes in the Western Mediterranean Sea

Diversité des parcours familiaux et rapport au temps

Cet article met en évidence, à partir d’une analyse de seize récits de vie de femmes collectés dans une région française en 2002-2003, que le sens attribué par les individus à leurs parcours familiaux dépend essentiellement de leur rapport au temps. Trois rapports au temps, qui caractérisent une forme d’individuation ou de rapport de l’individu à la société, ont ainsi été observés. Le premier est placé sous le signe de la continuité et de la tradition; l’organisation familiale y relève du groupe, et l’individu n’existe qu’en référence à ce dernier. Le second, qui est partie prenante de l’organisation familiale moderne, est placé sous le signe du projet de maîtrise de l’existence; l’individu cherche à conquérir son autonomie à travers la suite de ses expériences existentielles. Le troisième, enfin, au sein duquel l’individu ne se veut plus seulement autonome mais encore littéralement autoréférentiel, conduit l’acteur social au refus de toutes les contraintes extérieures et, paradoxalement, à nier le temps, si ce n’est dans sa dimension d’immédiateté, définissant ainsi une individualité contemporaine dans tous les sens du terme.Analysing the life-histories of 16 women collected in a region of France in 2002-03, this article reveals that the meaning individuals give to their family history is based on the meaning they give to time. Three notions of time characterising a type of individuation or relationship of the individual to society were found. The first is founded on continuity and tradition; the organisation of the family depends on the group and the individual exists only in relation to the group. The second—an expression of modern family organisation—is characterised by a focus on mastering one’s life; the individual seeks her autonomy in her own existential experiences. Finally in the third the individual tries not only to be autonomous but also literally self-referential. She refuses to accept any external constraints and, ironically, denies time except as it is simply a dimension of the present. In this way the person defines a contemporary individuality in the full meaning of the term

Experimental and numerical investigation on mixing and axial dispersion in Taylor-Couette flow patterns

Taylor-Couette flows between two concentric cylinders have great potential applications in chemical engineering. They are particularly convenient for two-phase small scale devices enabling solvent extraction operations. An experimental device was designed with this idea in mind. It consists of two concentric cylinders with the inner one rotating and the outer one fixed. Moreover, a pressure driven axial flow can be superimposed. Taylor-Couette flow is known to evolve towards turbulence through a sequence of successive hydrodynamic instabilities. Mixing characterized by an axial dispersion coefficient is extremely sensitive to these flow bifurcations, which may lead to flawed modelling of the coupling between flow and mass transfer. This particular point has been studied using experimental and numerical approaches. Direct numerical simulations (DNS) of the flow have been carried out. The effective diffusion coefficient was estimated using particles tracking in the different Taylor-Couette regimes. Simulation results have been compared with literature data and also with our own experimental results. The experimental study first consists in visualizing the vortices with a small amount of particles (Kalliroscope) added to the fluid. Tracer residence time distribution (RTD) is used to determine dispersion coefficients. Both numerical and experimental results show a significant effect of the flow structure on the axial dispersion

Mixing and axial dispersion in Taylor–Couette flows: the effect of the flow regime

The paper focuses on mixing properties of different Taylor–Couette flow regimes and their consequence on axial dispersion of a passive tracer. A joint approach, relying both on targeted experiments and numerical simulations, has been used to investigate the interaction between the flow characteristics and local or global properties of mixing. Hence, the flow and mixing have been characterized by means of flow visualization and simultaneous PIV (Particle Imaging Velocimetry) and PLIF (Planar Laser Induced Fluorescence) measurements, whereas the axial dispersion coefficient evolving along the successive flow states was investigated thanks to dye Residence Time Distribution measurements (RTD). The experimental results were complemented, for each flow pattern, by Direct Numerical Simulations (DNS), allowing access to 3D information. Both experimental and numerical results have been compared and confirmed the significant effect of the flow structure (axial wavelength of Taylor vortices and azimuthal wavenumber) on axial dispersion

Experimental study of enhanced mixing induced by particles in Taylor–Couette flows

Local mixing dynamics was recently investigated experimentally in Taylor–Couettesingle-phase flow, thanks to simultaneous Particle Image Velocimetry (PIV) and PlanarLaser-Induced Fluorescence (PLIF) techniques. The results highlighted the influence of thesuccessive flow bifurcations and the role of azimuthal wave states on the dispersion of dyeinjected in Taylor–Couette flows.The present work extends this study to two-phase configurations with spherical solidparticles. The respective effect of particle size and concentration on the vortices size andtransition thresholds between the various flow regimes has been examined thanks to flowvisualizations and PIV measurements. These hydrodynamic features have been comple-mented with PLIF experiments, that revealed a drastic enhancement of mixing due to thepresence of particles regardless of the flow regime, highlighting the existence of significantparticle-induced mixing in Taylor–Couette flows