968 resultados para Play groups statistics


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The class of all locally quasi-convex (lqc) abelian groups contains all locally convex vector spaces (lcs) considered as topological groups. Therefore it is natural to extend classical properties of locally convex spaces to this larger class of abelian topological groups. In the present paper we consider the following well known property of lcs: “A metrizable locally convex space carries its Mackey topology ”. This claim cannot be extended to lqc-groups in the natural way, as we have recently proved with other coauthors (Außenhofer and de la Barrera Mayoral in J Pure Appl Algebra 216(6):1340–1347, 2012; Díaz Nieto and Martín Peinador in Descriptive Topology and Functional Analysis, Springer Proceedings in Mathematics and Statistics, Vol 80 doi:10.1007/978-3-319-05224-3_7, 2014; Dikranjan et al. in Forum Math 26:723–757, 2014). We say that an abelian group G satisfies the Varopoulos paradigm (VP) if any metrizable locally quasi-convex topology on G is the Mackey topology. In the present paper we prove that in any unbounded group there exists a lqc metrizable topology that is not Mackey. This statement (Theorem C) allows us to show that the class of groups satisfying VP coincides with the class of finite exponent groups. Thus, a property of topological nature characterizes an algebraic feature of abelian groups.

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Tese (doutorado)—Universidade de Brasília, Instituto de Psicologia, Programa de Pós-Graduação em Processos de Desenvolvimento Humano e Saúde, 2016.

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A counterpart of the Mackey–Arens Theorem for the class of locally quasi-convex topological Abelian groups (LQC-groups) was initiated in Chasco et al. (Stud Math 132(3):257–284, 1999). Several authors have been interested in the problems posed there and have done clarifying contributions, although the main question of that source remains open. Some differences between the Mackey Theory for locally convex spaces and for locally quasi-convex groups, stem from the following fact: The supremum of all compatible locally quasi-convex topologies for a topological abelian group G may not coincide with the topology of uniform convergence on the weak quasi-convex compact subsets of the dual groupG∧. Thus, a substantial part of the classical Mackey–Arens Theorem cannot be generalized to LQC-groups. Furthermore, the mentioned fact gives rise to a grading in the property of “being a Mackey group”, as defined and thoroughly studied in Díaz Nieto and Martín-Peinador (Proceedings in Mathematics and Statistics 80:119–144, 2014). At present it is not known—and this is the main open question—if the supremum of all the compatible locally quasi-convex topologies on a topological group is in fact a compatible topology. In the present paper we do a sort of historical review on the Mackey Theory, and we compare it in the two settings of locally convex spaces and of locally quasi-convex groups. We point out some general questions which are still open, under the name of Problems.

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Contemporary African agricultural policy embodies the African Green Revolution’s drive towards modernisation and commercialisation. Agroecologists have criticised this movement on ecological, social and political grounds. Northern Ghanaian fertiliser credit schemes provide a good example through which these critiques can be examined in a context where agricultural policy reflects the African Green Revolution’s ideals. This study aimed to determine the relationship of such credit schemes to farmers’ use of organic amendments, elucidate other factors related to organic amendment use, and comment on the relevance of this modernisation policy and its relationship to agroecology. A first research phase employed semi-structured key informant interviews. Qualitative data from these informed construction of a semi-structured questionnaire that was used in a survey of 205 farmers. Multistage sampling purposively identified five villages and selected farmers within who had joined government and donor-funded fertiliser credit schemes. The use of organic and inorganic amendments was compared to that of peers who had not taken part in such schemes. Quantitative data were used in binomial logistic regression, inferential and descriptive statistics. Qualitative data were content analysed. Credit group membership was associated with higher fertiliser application and yield, but had little influence on the extent of commercialisation. Farmers who applied organic amendments were 40% less likely to belong to a fertiliser credit scheme than not, indicating substitution between organic and inorganic fertilisers. Organic amendments were 40% more likely to be applied to compound farms than outfields and six times more likely to be applied by household heads than other household members. However, household heads also preferentially joined credit groups. This was part of an agroecological soil fertility management strategy. Household heads appreciated the soil moisture retention properties of organic amendments, and applied them to compound farms to reduce risk to their household food supply in a semi-arid environment. They simultaneously accessed fertiliser to enhance this household provisioning strategy. They appreciated the increased yields this achieved, yet complained that the repayment terms of credit schemes were unfair, fertiliser did not enhance yields in dry conditions and fertilisers were supplied late. Farmers’ use of credited fertiliser alongside their existing agroecological strategy is helpful to the extent that it raises yields, yet is problematic in that it conflicts with risk-reduction strategies based on organics. There is some potential for modernised and agroecological management paradigms to coexist. For fertiliser credit to play a role in this, schemes must use fairer repayment terms and involve a focus on simultaneous use of organic amendments.

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The study was developed as a teacher-research project during initial teacher education – Masters Degree of Early Childhood and Primary Education, in Portugal. It analysed the interactions between children of 3 to 6 years old, during the use of the computer as a free choice activity, confronting situations between peers of the same age and situations between peers of different ages. The focus of the analysis was the collaborative interactions. This was a qualitative study. Children could choose the computer, amongst other interest areas, and work for around an hour in pairs. In the computer, children used mainly educational games. During four weeks, the interactions between the pairs were audio recorded. Field notes and informal interviews to the children were also used to collect data. Eleven children were involved in the study with ages ranging from 3 to 6 years old. Baseline data on children’s basic computer proficiency was collected using the Individualized Computer Proficiency Checklist (ICPC) by Hyun. The recorded interactions were analysed using the types of talk offered by Scrimshaw and Perkins and Wegerif and Scrimshaw: cumulative talk, exploratory talk, disputational talk, and tutorial talk. This framework was already used in a study in an early childhood education context in Portugal by Amante. The results reveal differences in computer use and characterize the observed interactions. Seven different pairs of children's interactions were analysed. More than a third of the interactions were cumulative talk, followed by exploratory talk, tutorial talk and disputational talk. Comparing same and mixed age pairs, we observed that cumulative talk is the more present interaction, but in same age pairs this is followed by exploratory talk whereas in the mixed age pairs it is tutorial talk that has the second largest percentage. The pairs formed by the children were very asymmetrical in terms of age and computer proficiency. This lead to the more tutorial interactions, where one children showed the other or directed him/her on how to play. The results show that collaboration is present during the use of a computer area in early childhood education. The free choice of the children means the adults can only suggest pairing suited to specific interactions between the children. Another way to support children in more exploratory talk interactions could be by discussing the way the older children can help the younger ones beyond directing or correcting their work.

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Résumé : Contexte : Depuis la création des Groupes de médecine de famille (GMF), les infirmières peuvent assurer le suivi des personnes atteintes de maladies chroniques (MC). Il existe des écarts entre la littérature et la pratique. Un constat provincial permettra une compréhension des enjeux d’optimisation de la pratique infirmière auprès de cette clientèle grandissante. Objectifs : 1) décrire les activités de l’infirmière en GMF auprès des personnes atteintes de MC; 2) décrire les éléments contextuels déterminants de ces activités; 3) dresser un portrait provincial des activités des infirmières de GMF auprès des personnes atteintes de MC. Méthode : Un devis mixte séquentiel exploratoire en trois volets a été effectué. Volet 1 : Une étude de cas multiple a été réalisée auprès de dix infirmières de GMF. Cinq sources de données ont été utilisées : 1) observation des rencontres infirmière-patient (n=10); 2) entrevues individuelles avec chaque infirmière (n=10); 3) entrevues individuelles avec chaque patient (n=10); 4) audit des notes infirmières au dossier des patients participant (n=10) et; 5) documents administratifs décrivant la pratique des infirmières à l’intérieur des GMF. L’analyse qualitative a permis de générer une liste d’activités et de décrire les éléments contextuels qui déterminent les activités. Volet 2 : Un questionnaire électronique a été créé à l’aide de la liste d’activités produite lors du Volet 1 et de la recension des écrits. Il a été validé et prétesté. Volet 3 : Une enquête provinciale a été réalisée auprès de 322 infirmières de GMF. Des analyses descriptives telles que des fréquences, moyennes, étendues et écarts types ont été effectuées. Résultats : Volet 1 : les activités des infirmières de GMF auprès des personnes atteintes de MC sont regroupées en cinq domaines. Des éléments liés à l’organisation, aux infirmières et aux personnes atteintes de MC peuvent influencer les activités. Volet 3 : 266 infirmières ont complété le questionnaire. Les résultats démontrent que leurs activités se situent principalement dans les domaines de la Promotion de la santé et de l’Évaluation globale de la condition de la personne. Les activités en lien avec la Collaboration infirmière-médecin et l’Organisation de l’offre de services sont réalisées de façon occasionnelle. Conclusion : Cette étude a permis une description en profondeur des activités des infirmières de GMF auprès des personnes atteintes de MC. Il s’agissait d’un jalon important en vue d’optimiser les interventions liées à la prise en charge des MC en soins de première ligne.