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Phytochemical Study of Two Medicinal Plants from Cameroon: Harungana madagascariensis and Bridelia micrantha; Chemical Transformations and Biological Activities of some Isolated Elements. Douze génotypes de pois (Asgrow, Jumbo, Lincoln, Merveille de Kelvedon, Purser, Rajai Torpe, Snajor Kosep Korai, Wando, Rondo, génotype local, Major Kosep Korai et Surgevil) ont été étudiés pour leur résistance aux maladies (Oïdium, mildiou, anthracnose, brunissement, jaunisse apicale) et leurs performances agronomiques (matières fraîches: racines, partie aérienne, nombre de branches fructifères/plante, nombre de fleurs/plante, nombre de gousses/plante, nombre de grains/gousse et rendements en grains/plante). La culture a été faite dans un milieu contrôlé (serre plastique) sur tourbe noire durant 5,5 mois (octobre à avril). Les résultats obtenus montrent que seul le génotype Purser est résistant à toutes les maladies et que le génotype Surgevil est sensible uniquement à la jaunisse apicale. Par contre, le génotype local est sensible aux trois maladies les plus fréquentes (Oïdium, Mildiou et Anthracnose). En ce qui concerne la croissance végétative, c'est le génotype Asgrow qui a synthétisé le plus de matière fraîche, deux fois plus que la matière fraîche synthétisée par le génotype Purser. Toutefois, le rendement élevé en matière fraîche ne contribue pas à un taux de nouaison élevé. En effet, seuls les génotypes ayant donné un rendement faible en matière fraîche (Snajor Kosep Korai, Asgrow, Major Kosep Korai, Rajai Torpe et Purser) ont eu le taux de nouaison le plus élevé, supérieur à 30%. Chez ce groupe, le bon rendement le plus élevé (> 9 g/plante) résulte du nombre de gousses/ plante (7,5 à 21,6) et du nombre de grains/gousse (2,8 à 4,92). De cette collection, le génotype Purser peut être retenu en raison de sa résistance à toutes les maladies et à ses bonnes performances agronomiques au profit des agriculteurs ou des programmes d'amélioration génétique.

"This article describes the main ingredients of a methodology currently under development for projecting families [in Canada]--these groups of individuals linked by conjugal ties or by blood--according to their principal characteristics: family type and number/ages of children. The crux of this methodology is a multidimensional model which can be viewed as an extension of the traditional cohort-components model that incorporates the conjugal and parity statuses of women. With an appropriate generalization of the conjugal status variable and the addition of an appendage for dealing with the special case of step families, this model eventually allows one to shift from the number of women according to demographic status (stemming from cross-classifying conjugal status and numbers of children present) to those families according to their main characteristics." (SUMMARY IN ENG AND SPA), (excerpt)

The development of multidimensional mathematical demography and its application to the analysis of such changes in life status as marriage, occupation, and migration is discussed. "This article presents an overview of the methods and models specific to this new branch. It stresses (1) their relationship with the methods and models of classical mathematical demography, (2) their field of application, (3) their elaboration, and (4) a few methodological and empirical questions raised by their use." (summary in ENG, SPA), (excerpt)

"To provide new insight into the evolution of multiregional population systems, this article presents a dynamic study of a nonlinear variant of the components-of-change model. In this variant, migrants out of a region do not distribute themselves among destination regions in constant proportions (as in the classical linear variant). Rather their allocation is proportional to that of population (weighted so as to account for the difficulty to move between regions). The analysis focuses on the existence, characteristics, and determination of equilibrium states. It is illustrated with an application to the population of Canada and its five large regions." (summary in ENG), (excerpt)

"This article presents an in-depth analysis of spatial-temporal characteristics of interprovincial migration in Canada carried out with longitudinal data obtained from the family allowance file. The methodology used calls on the log-linear model underlying the notion of the contingency table. This model permits a simple representation of the observed data, with the aid of parameters typical of the many possible interactions between the variables in question (variables of origin, destination and period in the present case)." The relative influence of the selected variables on migration is first assessed. "Second, this influence is further specified with the aid of a detailed investigation of the parameters that are relative to the quasi-independence variance, that is to say, the variance where only the effect of interaction between the three variables is ignored. Together with the suggestion that the variables of origin and destination are not independent (a result that confirms the need to emphasize interregional streams in the study of migration), this investigation sets forth some conclusions about the temporal variations of interprovincial migration." (summary in ENG, SPA), (excerpt)