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Background and Aims The Mediterranean Basin is one of the most important regions for the Earth's plant biodiversity; however, the scarcity of studies on fine scale patterns of genetic variation in this region is striking. Here, an assessment is made of the spatial genetic structure of all known locations of the three Sardinian endemic species of Aquilegia in order to determine the relative roles of gene flow and genetic drift as underlying evolutionary forces canalizing the divergence of Sardinian Aquilegia taxa, and to see if the spatial genetic structure found fits the current taxonomic differentiation of these taxa. Methods DNA from 89 individuals from all known locations of Aquilegia across Sardinia was analysed by means of amplified fragment length polymorphism (AFLP) markers. Both principal co-ordinates analysis (PCoA) and Bayesian clustering analyses were used to determine the spatial genetic structure irrespective of any taxonomic affiliation. Historical effects of gene flow and genetic drift were assessed by checking for the existence of isolation-by-distance patterns. Key Results STRUCTURE and PCoA analyses revealed a pattern of genetic variation geographically structured into four spatial genetic groups. No migration–drift equilibrium was detected for Aquilegia in Sardinia, when analysed either as a whole or in individual groups. The scenario approached a Case III pattern sensu Hutchinson and Templeton, which is associated with extreme isolation conditions where genetic drift has historically played a dominant role over gene flow. Conclusions The pattern of genetic variation of Sardinian taxa of Aquilegia indicates that genetic drift has been historically more influential than gene flow on population structure of Sardinian species of Aquilegia. Limited seed dispersal and divergent selection imposed by habitat conditions have been probably the main causes reinforcing post-Pleistocene geographical isolation of Aquilegia populations. The spatial genetic structure found here is not fully compatible with current taxonomic affiliations of Sardinian Aquilegia taxa. This is probably a consequence of the uncoupling between morphological and genetic patterns of differentiation frequently found in recently radiated taxa. [ABSTRACT FROM PUBLISHER]

Objectives: To compare colour Doppler (CD) versus power Doppler (PD) semiquantitative and quantitative scoring of synovial vascularisation and to evaluate the relationship between semiquantitative and quantitative scores in patients with rheumatoid arthritis (RA)., Methods: One hundred RA patients underwent B-mode, PD, and CD assessments of 12 joints at two European centres. Each joint with synovial hypertrophy (SH) detected on B-mode was semiquantitatively scored (0-3) for PD (SPD score) and CD (SCD score) synovial signal. PD and CD synovial signal were also quantitatively scored (0-100%) (QPD and QCD scores, respectively) using a software integrated in the US equipment for counting the colour fraction., Results: We found SH in 184 joints. SPD and SCD agreed in 92.3% (95%CI: 88.4; 96.2%) of paired scores, with Kendall rank correlation coefficient tau-b=0.95. QPD and QCD scores were highly correlated (Pearson's coefficient=0.70) but Blamd-Altman plot showed insufficient agreement, being the QCD scores systematically slightly higher than the QPD scores. The comparison of mean values of QPD and QCD between scores of SPD and SCD, respectively, showed significant differences between grade 0 and grade 1 (p<0.001), and grade 2 and grade 3 (p=0.042 and p=0.007, respectively) but not between grade 1 and 2 (p=0.154 and p=0.150, respectively)., Conclusions: The SPD and SCD scores were concordant and the QPD and QCD scores highly correlated but were not concordant. There was an overlap between SPD and SCD mild and moderate scores regarding QPD and QCD scores.