2 resultados para partial transposition

em Repositório Científico da Universidade de Évora - Portugal


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Phylogeographic studies, which infer population history and dispersal movements from intra-specific spatial genetic variation, require expensive and time-consuming analyses that are not always feasible, especially in the case of rare or endangered species. On the other hand, comparative phylogeography of species involved in close biotic interactions may show congruent patterns depending on the specificity of the relationship. Consequently, the phylogeography of a parasite that needs two hosts to complete its life cycle should reflect population history traits of both hosts. Population movements evidenced by the parasite’s phylogeography that are not reflected in the phylogeography of one of these hosts may thus be attributed to the other host. Using the wild rabbit (Oryctolagus cuniculus) and a parasitic tapeworm (Taenia pisiformis) as an example, we propose comparing the phylogeography of easily available organisms such as game species and their specific heteroxenous parasites to infer population movements of definitive host/predator species, independently of performing genetic analyses on the latter. This may be an interesting approach for indirectly studying the history of species whose phylogeography is difficult to analyse directly.

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This article contributes to the literature by testing six research hypotheses regarding the impact of partial privatisation on firms' performance. We measure performance using Data Envelopment Analysis (DEA), the Malmquist Index and ratios related to labour productivity, profitability and capacity utilisation. We use the Wilcoxon Signed Rank test to compare the performance after privatisation with that before privatisation. The hypotheses are tested with data from a chain of Portuguese heritage hotels, partially privatised in 2003. We conclude that productivity growth after privatisation is superior to productivity growth before privatisation due to technological progress. However, due to a frontier regress observed in the privatisation year, total factor productivity and profitability deteriorated after privatisation. This suggests that both efficiency changes and frontier shifts should be taken into account in order to accurately assess the impact of privatisation.