Influence of swimming strategy on microorganism separation by asymmetric obstacles

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2013), 87

It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this ... [more ▼]

It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this rectification effect arises from the interaction between the swimmers and the noncentrosymmetric pillars, here we demonstrate numerically that its efficiency is strongly dependent on the detailed dynamics of the individual microorganism. In particular, for the case of run-and-tumble dynamics, the distribution of run lengths, the rotational diffusion, and the partial preservation of run orientation memory through a tumble are important factors when computing the rectification efficiency. In addition, we optimize the geometrical dimensions of the asymmetric pillars in order to maximize the swimmer concentration and we illustrate how it can be used for sorting by swimming strategy in a long array of parallel obstacles. [less ▲]

Numerical investigation and experimental validation of physically-based advanced GTN model for DP steels

in Materials Science & Engineering : A (2013), 569

This numerical investigation of an advanced Gurson-Tvergaard-Needleman (GTN) model is an extension of the original work of [Ben Bettaieb, M., Lemoine, X., Bouaziz, O., Habraken, A.-M., Duchêne, L ... [more ▼]

This numerical investigation of an advanced Gurson-Tvergaard-Needleman (GTN) model is an extension of the original work of [Ben Bettaieb, M., Lemoine, X., Bouaziz, O., Habraken, A.-M., Duchêne, L., Numerical modeling of damage evolution of DP steels on the basis of X-ray tomography measurements, Mechanics of Materials 43 (2011) 139-156]. The current damage model extends the previous version by integrating the three damage mechanisms: nucleation, growth and coalescence of voids. Physically-based void nucleation and growth laws are considered, including an effect of the kinematic hardening. [less ▲]

The “soy-ization” of Argentina: dynamics of the “globalized” privatization regime in a peripheral context

in Technology in Society (2013), 35(2),

Based on extensive fieldwork conducted with actors from public, private and associative sectors, we explore the expansion of genetically modified soy in Argentina and we aim to figure out how the ... [more ▼]

Based on extensive fieldwork conducted with actors from public, private and associative sectors, we explore the expansion of genetically modified soy in Argentina and we aim to figure out how the neoliberal “globalized privatization regime” unfolded in a peripheral location. Our case points at two inherent contradictions with such a regime’s main tenets, namely that it needs a weak antitrust policy (thus leading to a market situation dominated by a monopoly of transnational companies) and a hyper-restrictive system of intellectual property. We highlight the participation of two groups of local actors in the regime. The first group is aligned with the globalized privatization regime agendas, while the second is involved in protest and regulatory actions focusing on the health, environment and safety issues related to the GM soy complex. To a different extent, both groups share a local agenda of resistance and an anti-imperialist imaginary. Both have national development objectives of Argentina in their ideological roots, although their conceptions of “development” are different (industrial development vs. protection of peasants’ life and the environment). We conclude that it is not enough to postulate that the neoliberal globalized privatization regime will just expand to the South as it did in Northern countries. Rather, combined with the commercialization of science, peripherality creates protest, activism and local regulation. [less ▲]

La charge vocale : De sa quantification à l’étude de son impact sur la fonction phonatoire et sur la qualité vocale

Doctoral thesis (2013)

Ce travail étudie la charge vocale principalement chez les enseignants. La prévalence élevée des troubles de la voix chez ces professionnels serait en partie liée aux trois facteurs principaux de charge ... [more ▼]

Ce travail étudie la charge vocale principalement chez les enseignants. La prévalence élevée des troubles de la voix chez ces professionnels serait en partie liée aux trois facteurs principaux de charge vocale que sont la durée de phonation, le niveau de pression sonore, et la fréquence vocale. Ces facteurs sont associés à des contraintes mécaniques appliquées aux plis vocaux lors de la vibration, potentiellement responsables de microtraumatismes du tissu, et participant au développement de lésions bénignes. Notre contribution intervient à deux niveaux d’étude de la charge vocale. Dans un premier temps, nous l’avons quantifiée en situation écologique dans une population d’enseignantes, en comparant deux niveaux de l’enseignement ordinaire belge : le maternel et le primaire. A cette fin, le comportement vocal de 12 enseignantes du maternel et de 20 enseignantes du primaire a été enregistré durant une semaine de travail, à l’aide d’un système de dosimétrie. Les objectifs étaient, d’une part, de déterminer les différences d’utilisation vocale selon le niveau d’enseignement, et d’autre part, de comparer l’utilisation vocale professionnelle et extra-professionnelle des enseignantes. Globalement, nos résultats montrent une charge vocale plus élevée en situation professionnelle qu’en situation extra-professionnelle. Par ailleurs, les enseignantes du maternel présentent une charge vocale plus élevée que celles du primaire, en termes de nombre de cycles vibratoires et de distance parcourue par les plis vocaux. Dans un deuxième temps, nous avons étudié l’impact de la charge vocale sur la fonction phonatoire et sur la qualité vocale en condition de laboratoire. Une première condition expérimentale avait pour but d’améliorer la compréhension des facteurs de durée et d’intensité de la charge vocale, en soumettant 50 femmes normophoniques à 2 heures de charge, réalisées à deux reprises en variant le niveau d’intensité. Une seconde condition expérimentale avait pour but de comparer les effets de 2 heures de charge chez 16 enseignantes normophoniques et 16 enseignantes dysphoniques. Les effets de la charge vocale ont été évalués à l’aide de mesures objectives et subjectives. Les principaux résultats montrent plus d’impact de la durée que de l’intensité de la charge sur les paramètres observés. Par ailleurs, peu de différences sont observées entre les deux groupes d’enseignantes au cours de la tâche de charge, suggérant que les enseignantes dysphoniques présentent une bonne résistance durant la charge. [less ▲]

L'enfant parentifié et sa famille

Book published by Erès (2013)

Le concept de parentification est, paradoxalement, aussi largement utilisé que méconnu. La rareté des ouvrages sur ce phénomène a contribué à le maintenir dans une sorte de flou, rendant complexe son ... [more ▼]

Le concept de parentification est, paradoxalement, aussi largement utilisé que méconnu. La rareté des ouvrages sur ce phénomène a contribué à le maintenir dans une sorte de flou, rendant complexe son identification. Ce que l’on sait de l’enfant parentifié, c’est qu’il assume des responsabilités importantes au sein de sa famille. Reste alors à savoir lesquelles. L’émergence et le développement des nouvelles formes familiales semblent interroger constamment la question des responsabilités de l’enfant. Que ce soit dans une famille post-divorce, monoparentale, recomposée ou primo-arrivante, dès que l’enfant vient en aide à son parent, la question de la parentification apparaît. Le risque est alors tout autant de voir des parentifications où elles n’existent pas, stigmatisant certaines formes familiales, que de passer à côté de réelles et sévères parentifications. Stéphanie Haxhe nous livre ici ses observations issues à la fois de la clinique et de la recherche. A travers les différents chapitres, elle décrit la parentification comme un processus, avec les facteurs participant à son apparition et/ou sa disparition, et propose une grille servant à en faciliter l’identification. Des pistes d’intervention sont proposées et illustrées par des situations cliniques et des références cinématographiques. La fratrie, généralement absente des écrits sur la parentification, tient également une place centrale et est abordée dans son organisation et ses ressources. [less ▲]

Is ultra-short cold ischemia the key to ischemic cholangiopathy avoidance in DCD-LT?

in Acta Chirurgica Belgica (2013, May), Supplement 113(3), 6729

Biogeochemistry and carbon mass balance of a coccolithophore bloom in the northern Bay of Biscay (June 2006)

Poster (2013, May)

Primary production (PP), calcification (CAL), bacterial production (BP) and dark community respiration (DCR) were measured along with a set of various biogeochemical variables, in early June 2006, at ... [more ▼]

Primary production (PP), calcification (CAL), bacterial production (BP) and dark community respiration (DCR) were measured along with a set of various biogeochemical variables, in early June 2006, at several stations at the shelf break of the northern Bay of Biscay. The cruise was carried out after the main spring diatom bloom that, based on the analysis of a time-series of remotely sensed chlorophyll-a (Chl-a), peaked in mid-April. Remotely sensed sea surface temperature (SST) indicated the occurrence of enhanced vertical mixing (due to internal tides) at the continental slope, while adjacent waters on the continental shelf were stratified, as confirmed by vertical profiles of temperature acquired during the cruise. The surface layer of the stratified water masses (on the continental shelf) was depleted of inorganic nutrients. Dissolved silicate (DSi) levels probably did not allow significant diatom development. We hypothesize that mixing at the continental slope allowed the injection of inorganic nutrients that triggered the blooming of mixed phytoplanktonic communities dominated by coccolithophores (Emiliania huxleyi) that were favoured with regards to diatoms due to the low DSi levels. Based on this conceptual frame, we used an indicator of vertical stratification to classify the different sampled stations, and to reconstruct the possible evolution of the bloom from the onset at the continental slope (triggered by vertical mixing) through its development as the water mass was advected on-shelf and stratified. We also established a carbon mass balance at each station by integrating in the photic layer PP, CAL and DCR. This allowed computation at each station of the contribution of PP, CAL and DCR to CO2 fluxes in the photic layer, and how they changed from one station to another along the sequence of bloom development (as traced by the stratification indicator). This also showed a shift from net autotrophy to net heterotrophy as the water mass aged (stratified), and suggested the importance of extracellular production of carbon to sustain the bacterial demand in the photic and aphotic layers. [less ▲]

Fecal calprotectin concentrations in adult dogs with chronic diarrhea.

in American Journal of Veterinary Research (2013), 74 (5)

La conciliation vie privée-vie professionnelle des gestionnaires hommes et femmes : le cas d'une société de transport québécoise

in @GRH (2013), 2013/1 (n°6)

While the professional category of managers presents special characteristics, one of them being important temporal obligations, we may ask whether men and women managers articulate work and life and ... [more ▼]

While the professional category of managers presents special characteristics, one of them being important temporal obligations, we may ask whether men and women managers articulate work and life and establish priorities in different ways. Wanting to look into this question, we focused on managers or executives and did so in a predominantly male environment, that of a transport company in Quebec. Our research question can be formulated as follows: "How do men and women managers with different family situations reconcile their private and professional lives?” In order to answer this question and attain our various research objectives, we studied a male dominated sector. We mobilized the qualitative technique of semi-structured interviews and met with 17 managers, including 8 men and 9 women in the company. While this qualitative research is mainly exploratory, our results show that men and women managers prioritize in different ways. However, we observed an increased willingness of men to have more time for family. In contrast, gender has no impact on the use of organizational measures to reconcile professional and private life. Thus, gender is not, in itself, a dominant variable influencing the practices of reconciling private and professional lives of managers, as other factors such as socio-professional category, the sector, the nature of the position, family characteristics, etc. also play a role and from this point of view, women and men experience similar situations. Our research highlights interesting temporal strategies of managers, one which is based on a hierarchy of time availability and another on the preservation of private/family times. [less ▲]

Compte-rendu de l'ouvrage de D. Pradelle, Par-delà la révolution copernicienne. Sujet transcendantal et facultés chez Kant et Husserl

in Bulletin d'Analyse Phénoménologique (2013), IX(3), 1-5