Evolution psychodynamique à moyen terme du processus vocationnel chez le grand adolescent. Motivation

Doctoral thesis (1995)

In the Preface of their Research, the author examines from a theorical point of view the problem of motivation.

Evolution psychodynamique à moyen terme de la détermination vocationnelle chez le grand adolescent

Doctoral thesis (1995)

Introduction , Conclusions and Defence.

Hydrodynamic simulations of galaxy formation

in Dark Matter (1995, July)

We have developed an accurate, one-dimensional, spherically symmetric, Lagrangian hydrodynamics/gravity code, designed to study the effects of radiative cooling and photo-ionization on the formation of ... [more ▼]

We have developed an accurate, one-dimensional, spherically symmetric, Lagrangian hydrodynamics/gravity code, designed to study the effects of radiative cooling and photo-ionization on the formation of protogalaxies. We examine the ability of collapsing perturbations to cool within the age of the universe. In contrast to some studies based on order-of-magnitude estimates, we find that cooling arguments alone cannot explain the sharp upper cutoff observed in the galaxy luminosity function. We also look at the effect of a photoionizing background on the formation of low-mass galaxies. [less ▲]

Polylactide microparticles prepared by double emulsion-evaporation 2 : Effect of the poly(lactide-co-glycolide) composition on the stability of the primary and secondary emulsions

in Journal of Colloid and Interface Science (1995), 173(1), 55-65

Polylactide and copolymers with glycolide have been used as coating polymers in the microencapsulation technique based on the W1/o/w2 double emulsion-evaporation method. Stability of the primary emulsion ... [more ▼]

Polylactide and copolymers with glycolide have been used as coating polymers in the microencapsulation technique based on the W1/o/w2 double emulsion-evaporation method. Stability of the primary emulsion is of critical importance and clearly predetermines the internal morphology of the microspheres, in agreement with the very fast hardening of the oil phase (CH2Cl2) as soon as the primary emulsion is dispersed in water. When the peptide or' protein to be encapsulated is able to interact with the coating polymer and possibly with the surfactant, the stabilization mechanism of the primary emulsion is very complex. It has been shown that the interaction of BSA (bovine serum albumin) with the polyester is as strong as the glycolide content is high, which results in the formation of a solid film at the w1/o interface and in a high emulsion stability. Addition of a surfactant, such as poloxamer 188, in the oil phase has a deleterious effect on both the emulsion stability and the internal structure of the microspheres. Use of a dye tracer in the internal aqueous phase was not useful in probing the double emulsion stability and the encapsulation efficiency, because of specific interactions between the dye (indigocarmine) and the coating polyester. [less ▲]

The SEVEX project : An integrated numerical model for the dispersion of gas in a complex terrain

in Loss Prevention Colloquium (1995, June)

An interdisciplinary numerical model to investigate different potential accidental scenarios on chemical plants is presented. The dispersion of the pollutants is simulated by a lagrangian particle ... [more ▼]

An interdisciplinary numerical model to investigate different potential accidental scenarios on chemical plants is presented. The dispersion of the pollutants is simulated by a lagrangian particle diffusion model to investigate the impacts of potential releases of pollutants from chemical plants in a complex terrain [less ▲]

Métapsychologie de l'adolescence

in Cahiers du CEP (Centre d'Etudes Pathoanalytiques) (1995), 5(2), 71-104

Before 1960 there was very few psychoanalytical litterature about adolescence. Since 50 years, there is plenty of articles on that subject. The author comments the most important psychoanalytical writers ... [more ▼]

Before 1960 there was very few psychoanalytical litterature about adolescence. Since 50 years, there is plenty of articles on that subject. The author comments the most important psychoanalytical writers who brought a new and useful thought thereabout. [less ▲]

Short-term memory, articulation rate and subvocal rehearsal in Down's syndrome

Poster (1995, May 12)

Gathercole (1994) show that in normal young children there is no significant link between articulation rate and immediate memory span, but that these variables are closely related in adults. These results ... [more ▼]

Gathercole (1994) show that in normal young children there is no significant link between articulation rate and immediate memory span, but that these variables are closely related in adults. These results are in contradiction with the short-term memory development hypotheses stated by the working memory model. According to these hypotheses, children are sensitive to word-length effect providing that stimuli are presented auditorily. We also know that word-length effect is strongly related to articulation rate and to subvocal rehearsal. This conception of mnemonic development has been recently challenged. Some authors show that, in adults, word-length effect can be a consequence of the delay at recall. According to Gathercole, the same conclusion can be applied to results obtained with children : word-length effect can be due to delay at recall of long words rather than to the utilization of subvocal rehearsal. Previous studies seem to confirm this hypothesis by showing that children are not affected by articulatory suppression. These results have clear implications for the short-term memory development hypothesis. It seems that in spite an strong word-length effect, children do not rehearse during auditory memory span tasks. The following experiments are based: (1) on the assumption that mental retarded individuals do not rehearse and (2) on the highly significant word-length effect in our Down's syndrome subjects. Our hypothesis, as Gathercole's one, is that if subjects really rehearse, then memory span and articulation rate will be highly correlated. [less ▲]

Heavy elements in halo stars: the r/s-process controversy.

in Astronomy and Astrophysics (1995), 297

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis ... [more ▼]

It has been suggested by Truran (1981) that rapid neutron captures (the r-process) dominate the production of heavy elements in very metal-poor stars. Several spectroscopic works analyzing that hypothesis are reviewed and rediscussed and it is shown that there is, in fact, no secure observational evidence in support of Truran's suggestion. A method to determine the odd-to-even isotopic ratio of barium, and thus to estimate the relative contributions of the r and s-processes, is presented. It takes advantage of the hyperfine structure affecting the spectral lines of the odd isotopes to distinguish them from the even isotopes. This method, applied to the classical metal-poor subgiant HD 140283, shows that the barium isotopic ratio in that star is in agreement with a pure s-process production, and excludes any significant enhancement of the r-process contribution, in disagreement with previous works based on elemental abundances. [less ▲]

Effects of an observation training program on feedback. Study of several cases

in Paré, Claude (Ed.) Better teaching in physical education? Think about it! (1995, May)

As frequently pointed out, information given to learners about their performance favourably influences their achievement. This was confirmed in the motor learning area and was also found in several ... [more ▼]

As frequently pointed out, information given to learners about their performance favourably influences their achievement. This was confirmed in the motor learning area and was also found in several studies dealing with teaching effectiveness. These studies have reinforced the significance of feedback for teachers eager to improve the performance of their pupils. ... [less ▲]

Marx aujourd'hui

Article for general public (1995)