L'aménagement villageois sylvo-pastoral de la formation de brousse tachetée de Tientiergou (arrondissement de Say)

Le schéma directeur d'approvisionnement en bois de la ville de Niamey (SIDAN) a été établi en 1991. Il a servi de base aux textes réglementaires et fiscaux et au démarrage des actions de développement des premiers marchés ruraux et des aménagements forestiers. Le premier site choisi pour tester les aménagements forestiers a été celui de Tientiergou, dans l'arrondissement de Say à 50 km au Sud de Niamey. L'objectif visé était de mettre au point les techniques d'exploitation des formations arbustives à Combrétacées, caractéristiques des plateaux de la périphérie de la ville de Niamey. Ces modes d'exploitation devaient à la fois garantir une bonne préservation du milieu et donner aux populations rurales les moyens de les préserver, soit par des plantations ou des actions de DRS/CES, soit par une meilleure gestion agricole de leurs terres. Après avoir fait l'historique des aménagements forestiers au Niger, cet article présente le contexte physique et social du massif forestier de Tientiergou (30 000 ha), la situation agricole et pastorale, enfin l'inventaire des ressources ligneuses réalisé préalablement à l'aménagement. Les zones aménagement de type orienté (sans aménagements forestiers) ont un coût faible, qui varie de 1 270 FCFA/ha (pour un terroir de 3 500 ha) à 4 430 FCFA/ha (pour un terroir de 1 000 ha). Les aménagements forestiers (marchés ruraux contrôlés) entraînent une augmentation de plus de deux fois ce coût ( de 3 840 à 8 440 FCFA/ha). (Résumé d'auteur

Systematic review: Impact of meningococcal vaccination on pharyngeal carriage of meningococci.

OBJECTIVE: To investigate the effect of meningococcal vaccines on pharyngeal carriage of meningococci. METHODS: Systematic review. MEDLINE and EMBASE were searched for relevant studies. Controlled trials and observational studies which used comparison groups or compared carriage rates before and after vaccination were included in the review. RESULTS: Twenty-nine studies satisfied the inclusion criteria. Twenty-five studies reported the effect of a polysaccharide vaccine, one the effect of a serogroup C conjugate vaccine and three the impact of serogroup B outer-membrane vaccines on overall and/or serogroup-specific meningococcal carriage rates. Ten studies of meningococcal polysaccharide vaccines found reduced serogroup-specific carriage; seven of these focussed on high-risk groups and had a short follow-up period. Only one of five studies of civilian populations in Africa showed a significantly reduced carriage. Many studies had methodological shortcomings. The one study which assessed the effect of a meningococcal conjugate vaccine on carriage showed a significant impact. Three studies of serogroup B outer-membrane protein vaccines showed no effect on carriage. CONCLUSIONS: A few well-designed trials of the impact of meningococcal vaccines on carriage have been undertaken. Such studies should be an essential component of the evaluation of new meningococcal vaccines, particularly those introduced to control epidemic meningococcal disease in Africa

Meningococcal carriage in the African meningitis belt.

In the African meningitis belt, epidemics of meningococcal disease occur periodically, although unpredictably, every few years. These epidemics continue to cause havoc but new efforts to control the disease, through the use of conjugate vaccines, are being made. Conjugate vaccines are likely to reduce meningococcal carriage, thus generating herd immunity, but to understand their potential impact we need to know more about the epidemiology of meningococcal carriage in Africa. We review published studies of meningococcal carriage in the African meningitis belt. A wide range of carriage prevalences has been reported, from 3% to over 30%, and the serogroup distribution has been variable. Factors influencing carriage include age, contact with a case, and the epidemic/endemic situation; however, season and immunisation with polysaccharide vaccine have little effect. Since the dynamics of carriage within a population are complex, longitudinal carriage studies are of great value; however, few such studies have been done. Carefully designed carriage studies are needed to measure and interpret the impact of meningococcal group A conjugate vaccines in Africa

Assessing constructive supervisor behavior: Development and evaluation of a brief follower-rated scale

Followers are thought to be keenly attuned to supervisor behaviors because these can affect their learning, well-being, and performance at work. However, a practical and empirically tested measure of constructive supervisor behaviors that are valued by followers is not available in the literature. We develop a Constructive Supervisor Behavior Scale (CSBS) that is suitable for human resource development purposes and we assess its psychometric properties across three studies. In Study 1, exploratory factor analysis is conducted on data collected from employees in New Zealand and the United States (N = 333). This resulted in a four-factor structure comprising ethical conduct, networking, clarifying, and recognizing behaviors. In Study 2, confirmatory factor analyses are used to assess the four-factor structure of the CSBS on New Zealand-based employees (N = 250). In Study 3, the convergent and discriminant validity of the CSBS are examined on office-based employees in the United States (N = 342); additional measurement invariance analyses are conducted with the New Zealand and U.S. samples