Cet article s'intéresse au rôle joué par l'intervention dans le processus d' empowerment de personnes en situation d'extrême pauvreté. Il se fonde sur une étude de cas d'une vingtaine de familles rejointes par le programme de santé publique Naître égaux – Grandir en santé (NÉ – GS). Il identifie d'abord les principales composantes qui se dégagent des processus d' empowerment observés. Par la suite, et c'est là le coeur de notre propos, l'article fait ressortir un certain nombre d'éléments pour qualifier l'intervention individuelle réalisée dans un tel contexte : une intervention à un moment clé de la vie ; une forte relation de confiance ; une intervention qui part du ou des projets des parents ; enfin, un accompagnement vers les services et ressources de la communauté en procurant le sentiment de posséder du pouvoir.

In vertebrates, only few experiments have been performed in microgravity to study the embryonic development from fertilization. To date, these concern only amphibian and fish. We report here a study on the embryonic development of Pleurodeles waltl (urodele amphibian) eggs oviposited in microgravity. The experiment was performed twice on board the Mir space station and the data obtained included video recording and morphological, histological and immunocytological analyses. The data confirm that the microgravity conditions have effects during the embryonic period, particularly during cleavage and neurulation, inducing irregular segmentation and abnormal closure of the neural tube. Moreover, we observed several abnormalities hither to undescribed corresponding to cortical cytoplasm movements, a decrease of cell adhesion and a loss of cells. These abnormalities were temporary and subsequently reversible. The young larvae that hatched during the flight displayed normal morphology and swimming behavior after landing. The results obtained in the urodele Pleurodeles waltl are in accordance with those observed earlier in the anuran Xenopus laevis and in the fish Oryzias latipes.

The study of the influence of weightlessness on fertilization and embryonic development of a vertebrate is of importance in the understanding of basic embryogenesis and in the preparation of the future exploration of space. Accordingly, specific hardware was designed to perform experiments on board the MIR space station with an amphibian vertebrate model, taking into account the biological requirements and the multiple constraints of a longterm space mission. This paper describes the biological uses and presents the technological specifications of the device developed under CNES management. The hardware was adapted to and is compatible with biological requirements as confirmed by three experiments performed in space on board the orbital MIR station.

The FERTILE experiment was twice performed onboard the MIR space station during the French Cassiopee and Pegase space missions. The aim of the study was to analyze microgravity effects on the fertilization and embryonic development, and then to study the further development on ground in the urodele amphibian Pleurodeles waltl. For this experiment, a spatial instrument was developed by the CNES and used to rear numerous eggs, embryos and the adults on trays in μG conditions, and several eggs and embryos on a 1G-rotating centrifuge. Numerous embryos were fixed during the flight. Some embryos were kept alive after landing. The young larvae with normal morphology and behavior hatched in microgravity as control animals on earth. Recovered on ground at post-hatching stage, young larvae reared at room temperature underwent metamorphosis and became mature without obvious abnormalities. The rate of development and morphology were analogous in these animals and in ground controls reared during a similar annual period. Analysis of offspring was performed. Born-in-space males were firstly mated with groundcontrol females, and then with born-in-space females. The mating gave progenies that normally developed. Depending on the techniques used and on the limits of the analyses, the works clearly demonstrated that these amphibian embryos born in space are able to live and reproduce after return on earth.

The FERTILE experiment was twice performed onboard the Mir space station during the Cassiopée and Pégase French space missions. The goal was to analyze the effects of microgravity on fertilization and embryonic development, and then on further development on the ground in the amphibian Pleurodeles waltl . The present paper reports development that occurred in the laboratory after landing. Recovered on the ground at the hatching stage, young larvae reared at room temperature underwent metamorphosis and became adults without obvious abnormalities. Of particular interest was the rearing temperature that induced a delayed metamorphosis for animals from the Cassiopée space mission, but not for animals from the Pégase mission. The rate of development and the morphology were analogous in these animals and in ground controls reared in a similar annual period. Analysis of offspring was performed using these animals. Males born in space were first mated with control ground‐born females and then with females born in space. The mating gave progeny that developed normally. Depending on the methods used and on the limits of the analyses, the results clearly demonstrated that animals born in space were able to live and reproduce after return to the ground.

Effects of microgravity (microG) on fertilization were studied in the urodele amphibian Pleurodeles waltl on board the MIR space station. Genetic and cytomorphologic analyses ruled out parthenogenesis or gynogenesis and proved that fertilization did occur in microG. Actual fertilization was demonstrated by the analysis of the distribution of peptidase-1 genes, a polymorphic sex-linked enzyme, in progenies obtained in microG. Further evidence of fertilization was provided by the presence of spermatozoa in the perivitelline space and in the fertilization layer of the microG eggs and by the presence of a female pronucleus and male pronuclei in the egg cytoplasm. Experiments in microG and in 1.4G, 2G, and 3G hypergravity showed for the first time that, compared to eggs in 1G, several characteristics of the fertilization process including the cortical reaction and the microvillus transformations were altered depending on the gravitational force applied to the eggs. Microvillus elevation, the most evident feature, was reduced on microG-eggs and amplified on eggs submitted to 2G and 3G. No lethal consequences of these alterations on the early development of microG-eggs were observed.

A research group in our laboratories works on development of amphibians under microgravity conditions. Several experiments were performed in space conditions using embryos or adults of the urodele amphibian, Pleurodeles waltl ( Bautz et al ., 1995 ; Dournon et al., 1997; Husson et al., 1998; Duprat et al., 1998; Aimar et al., 2000 ). In 1999, for the so-called Perseus French space mission onboard the MIR space station, the project was to rear embryos and larvae of Pleurodeles waltl in microgravity conditions to study the appearance and evolution of otoconia in the inner ear (Oukda et al., 1999a and b). The present paper reports the technique used to feed and rear Pleurodeles larvae in microgravity conditions with the assistance of a cosmonaut.

In Pleurodeles waltl and Pleurodeles poireti, one of the two genes encoding the peptidase-1, the gene pep-1 beta or its allele pep-1B are located on the chromosomes W and Z respectively. The gene pep-1A is either linked to chromosome Z in P. waltl or to chromosome W in P. poireti. From our results concerning sex reversals by heat treatment and from study of the two species in the wild, we propose that the gene pep-1 beta has all African origin, as have P. poireti and some P. waltl, and on the other hand, that its allele pep-1B has an european origin. P. waltl and P. poireti could provide from a reciprocal exchange between the sex chromosomes Z and W which could have occured in north africa before the pliocene age. So, before the formation of the Gibraltar strait, some P. waltl could have colonized the north of Africa from what will become iberic peninsula. Because of its isolation, the gene pep-1B could have evolved to give the allele pep-1 beta.

In September 1991, we began to evaluate three Healthy Cities initiatives in the Montreal area using a holistic approach, based on the theory of negotiated mode of action. We are experimenting with an interactive evaluation method which aims to involve participants in the process and to help them gain a better understanding of their project. Two techniques are being used to concretize the process: a steering committee who interpret the data collected throughout the process and a newsletter that outlines the results to participants at all sites.This paper describes how three elements of the Healthy Cities concept-sharing of common objectives, intersectoral action and citizen participation-are being implemented at the three sites being analyzed. We will show that the three initiatives underline the negotiation process that must be respected to maintain the balance between the objectives of intersectoral action and citizen participation. Preliminary results also show the importance of the healthy public policies strategy that should be analyzed as one part of a three-headed concept with the two precedent objectives. We will discuss also the requirements of an interactive evaluation approach, both for the evaluators and 'evaluatees'. Evaluators must be able to communicate, motivate and negotiate and participants must take an interest in the evaluation process and agree to listen to opinions on the development of their project that may be different from their own views.

SummaryUp to now, no case of spontaneous sex reversal has been described in the urodele amphibianPleurodeles waltlreared at ambient temperature. However in offspring reared under laboratory conditions, males, females but also intersex individuals were obtained. The males, some females and the intersexes had the ZZ male genotype identified through a test performed with a sex-linked enzyme. The other females had the ZW female genotype. Using the animals of this particular strain, an offspring analysis was made on crosses between, respectively, ZZ males and ZW females, ZZ males and ZZ females, and ZZ intersexes and ZZ males or females. All these crosses gave ZZ males, ZZ females and ZZ intersexes. The spontaneous complete or partial sex reversal is inheritable, but the genetic mechanism of this inheritance has not yet been elucidated.

Two biological spatial experiments : TORCOL and FERTILE, have been developped by the Laboratory of experimental Biology-Immunology, University Henri Poincare of Nancy (France), during the 1995 and 1996 years respectively.The TORCOL experiment has been embarked aboard the satellite Photon 10. The FERTILE experiment has been realized aboard the russian orbital station MIR during the CASSIOPEE mission