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41.
In May 2004, the European Union acquired not just ten new member states but several new neighbours. At about the same time, it began to flesh out a European Neighbourhood Policy (ENP) to bring some order to the EU's relations with its old and new neighbours and to ensure that the newly enlarged EU would be surrounded by a 'ring of friends'. The ENP is also supposed to stave off further enlargement to eastern Europe. However, several problems with the ENP are evident. It requires much of the neighbours and offers only vague incentives in return, making it unlikely that the ENP can meet its core objectives. Furthermore, the ENP is ambiguous about where the EU's borders will end, and it is already apparent that such ambiguity is not helping to foster reform in eastern Europe. Either the EU should say 'no' to further enlargement, so the ENP becomes the framework for relations with the neighbour for the foreseeable future, or it should say 'yes' to eventually letting in a specified number of neighbours which then move out of the ENP.  相似文献   
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The mangrove Rhizophora stylosa is believed to have been introduced to Moorea, French Polynesia, in about 1946, and has since spread to form dense single-species forests in former saltmarsh and lagoon fringing shrubland. Although it is having a significant ecological impact, it is possible to see this biological invasion as being of ecological benefit. There is even some evidence to suggest it may in fact represent a reintroduction (or even survival) of a native taxon. Some general issues arising from this local example are discussed.  相似文献   
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Records are presented of tropical drift disseminules reaching Southeast Australian beaches. About 22 species are represented and seeds of at least seven may retain viabiliry. Most species are widespread plants of tropical coastal regions of the Southwest Pacific, including Queensland although one does not grow in Australia Spatial and temporal varianbns in drip disseminule assemblages are described and comparisons made with assemblages in Fiji, Queensland and elrewhere. With consideration of current and wind pattern, they suggest that most tropical drift disseminules reaching New South Wales coasts derive from islands to the north and northeast, rather than from Queensland.  相似文献   
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Analyses of the locational and temporal spacing of periodic market-places have provided only partial confirmation of the hypothesis 'proximity in space implies separation in time.' The patterns, which are observed in almost all empirical studies, are explained here in terms of a simple avoidance rule constrained by the geometry of periodic market-place systems. The results of a series of simulations suggest that the constraints of geometry are such that only simple avoidance rules can be applied, and any more sophisticated rationale is therefore questionable.
Les études portant sur le degré de séparation spatiale et temporelle des places de marché périodique ne confirment que partiellement l' hypothése que proximité spatiale implique séparation dans le temps. Les effets observés dans presque toutes les études empiriques sont éxpliqués ici en terme d' une simple loi d' évitement, sous les contraintes de la géometrie du système des marchés périodiques. Les resultats d'une série d' analyses de simulations suggerent l' existence de contraintes géometriques telles que seules de simples lois d' evitement semblent opérationnelles. Ainsi, toute autre explication plus compliqué est remise en question.  相似文献   
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In Western democracies armed forces perform a variety of internal functions. This paper examines the principles and issues relating to the use of the Australian Defence Force in the enforcement of law against individual citizens and aliens. This function is normally the responsibility of the police but there are pressures in Australia and overseas for the wider use of armed forces in this field. Traditional restraints on the employment of armed forces in this capacity date back to parliamentary resistance to the power of the Crown. Several barriers, constitutional, legal and institutional, have developed to ensure that the executive cannot easily abuse its necessary control over the armed forces in a way that endangers civil liberties. While there is no serious danger of such abuse at present, several issues need to be monitored.  相似文献   
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In this study, research questions are formulated to investigate the determinants and consequences of the physical distances separating residents of government-assisted senior citizen apartment (SCA) projects and their adult children. Interview survey data were obtained from residents (n= 97) of three SCAS in suburban Winnipeg, Canada, and geographically matching baseline samples of community residents (n= 105). The analysis involves the use of bivariate statistical inferential tests and multiple regression frameworks. The results disclose that (1) greater parent-child separation distances are registered by SCA residents compared to the community elderly; (2) ‘distance of the most recent residential move’ is the most significant predictor of the intergenerational separation distances recorded by SCA residents; (3) spatial proximity is the most significant predictor of social interaction between SCA residents and their children. It is concluded that the results have important implications for (1) developmental models of elderly migration and (2) policies governing the provision of seniors' housing. Dans cette étude, on s'interroge sur les déterminants et les conséquences des distances physiques qui séparent les reéidents des programmes d'habitation pour personnes âgées (SCA) subventionnés par le gouvernement, et leurs enfants adultes. On a recueilli des données d'enquête en faisant des entrevues avec les résidents (n= 97) de trois SCA dans la banlieue de Winnipeg, Canada, et avec des résidents dans la communauté (n= 105) qui font partie des échantillons de référence appariés géographiquement. Pour analyser les données, on a utilisé des tests d'inférence statistique bivariés et des analyses de régression multiple. Les résultats démontrent les faits suivants: (1) les enfants des résidents des SCA sont séparés de leurs parents par une plus grande distance que les enfants des personnes âgées dans la communauté; (2) ? la distance du plus récent déménagement?est le prédicteur le plus important des distances de séparation intergénérationnelle; (3) la proximité spatiale est le prédicteur le plus significatif de l'interaction sociale entre les résidents des SCA et leurs enfants. Ces résultats comportent des conséquences importantes pour le développement des modèles de migration des personnes âgées, aussi bien que pour les politiques qui régissent le logement pour personnes âgées.  相似文献   
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