94 resultados para Barrington
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Mode of access: Internet.
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Nothofagus moorei (F. Muell.) Krasser has a disjunct and narrow distribution in south-eastern Australian cool temperate rainforest. To assess the conservation-genetic priorities for this species, the genetic diversity of 20 populations sampled from the largest remnant patches at northern and southern distributional extremes, the McPherson and Barrington ranges (a total of 146 individuals), was investigated by using inter simple sequence repeats (ISSR). Regeneration in northern regions of N. moorei has been documented to be predominantly by vegetative means, but our results indicate little evidence of clonality outside the multi-stemmed rings of trees. In addition, genetic diversity was considerably higher in the northern (McPherson, h = 0.1613) than in the southern range (Barrington, h = 0.1159), and genetic differentiation was significantly positively correlated with geographic distance in the former region, but not the latter. Total intraspecific variation was moderate, as measured by Shannon's diversity index, I = 0.2719, and Nei's gene diversity, h = 0.1672, and is considered at the high end of spectrum for estimates of narrow endemic species. An analysis of molecular variation indicated that the majority of genetic variation is partitioned among individuals within population (60%; P < 0.001), rather than among populations within regions (10%; P < 0.001). However, a large and significant component of the measured diversity was partitioned between northern and southern regions (29%; P < 0.001). Several hypotheses are outlined to explain these differences and management implications are discussed. However, given the narrow range, poor dispersal mechanism and restriction to cool temperate rainforest, the continued existence of N. moorei is most threatened by environmental instability and habitat loss resulting from global climate change. In this context the northern regions of the species are most at risk and extinction of such populations would lead to a significant loss of genetic variation for the species as a whole.
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The complexity of many organizational tasks requires perspectives, expertise, and talents that are often not found in a single individual. Organizations have therefore been placing employees into groups, assigning them to tasks they would formally have undertaken individually. The use of these groups, known as workgroups, has become an important strategy for managing this increased complexity. Empirical research on participative budgeting however has been limited almost exclusively to individuals. This dissertation empirically examines the effect of the information that management and workgroups have about group members' performance capabilities, on the work standards that workgroups select during the participative budgeting process. ^ A laboratory experiment was conducted in which two hundred and forty undergraduate business students were randomly assigned to three-member groups. The study provides empirical evidence which suggests that when management is unaware of group members' performance capabilities, workgroups select higher work standards and have higher performance levels than when management is aware of their performance capabilities. ^