7 resultados para historical and contemporary photography

em University of Queensland eSpace - Australia


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Genetic variation at microsatellite markers was used to quantify genetic structure and mating behavior in a severely fragmented population of the wind-pollinated, wind-dispersed temperate tree Fraxinus excelsior in a deforested catchment in Scotland. Remnants maintain high levels of genetic diversity, comparable with those reported for continuous populations in southeastern Europe, and show low interpopulation differentiation (Theta = 0.080), indicating that historical gene exchange has not been limited (Nm = 3.48). We estimated from seeds collected from all trees producing fruits in three of five remnants that F. excelsior is predominantly outcrossing (t(m). = 0.971 +/- 0.028). Use of a neighborhood model approach to describe the relative contribution of local and long-distance pollen dispersal indicates that pollen gene flow into each of the three remnants is extensive (46-95%) and pollen dispersal has two components. The first is very localized and restricted to tens of meters around the mother trees. The second is a long-distance component with dispersal occurring over several kilometers. Effective dispersal distances, accounting for the distance and directionality to mother trees of sampled pollen donors, average 328 m and are greater than values reported for a continuous population. These results suggest that the opening of the landscape facilitates airborne pollen movement and may alleviate the expected detrimental genetic effects of fragmentation.

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This paper explores issues arising from the welfare reform process in the United States and Australia. The involvement of faith-based organisations in both countries has evolved in different historical, social, political and cultural contexts. The paper will explore three main themes. First, it examines the relevance of the term 'faith-based' to describe the nature of the relationship between charities and churches in the mixed economy of welfare in the Australian context. Second, it provides a critical analysis of the reform processes, suggesting implications for the future of church-based organisations. Third, it maps directions for cross-comparative research of church-based social services provision in both countries.