Multilocus analysis of phylogeography and population history is a powerful tool

We explored the efficacy of species tree methods at the family level in birds, using the Australo-Papuan Fairy-wrens (Passeriformes: Maluridae) as a model system. Fairy-wrens of the genus Malurus are known for high intensities of sexual selection, resulting in some cases in rapid speciation. This history suggests that incomplete lineage sorting (ILS) of neutrally evolving loci could be substantial, a situation that could compromise traditional methods of combining loci in phylogenetic analysis. Using 18 molecular markers (5 anonymous loci, 7 exons, 5 introns, and 1 mitochondrial DNA locus), we show that gene tree monophyly across species could be rejected for 16 of 18 loci, suggesting substantial ILS at the family level in these birds. Using the software Concaterpillar, we also detect three statistically distinct clusters of gene trees among the 18 loci. Despite substantial variation in gene trees, species trees constructed using four different species tree estimation methods (BEST, BUCKy, and STAR) were generally well supported and similar to each other and to the concatenation tree, with a few mild discordances at nodes that could be explained by rapid and recent speciation events. By contrast, minimizing deep coalescences produced a species tree that was topologically more divergent from those of the other methods as measured by multidimensional scaling of trees. Additionally, gene and species trees were topologically more similar in the BEST analysis, presumably because of the species tree prior employed in BEST which appropriately assumes that gene trees are correlated with each other and with the species tree. Among the 18 loci, we also discovered 102 independent indel markers, which also proved phylogenetically informative, primarily among genera, and displayed a ∼4-fold bias towards deletions. As suggested in earlier work, the grasswrens (Amytornis) are sister to the rest of the family and the emu-wrens (Stipiturus) are sister to fairy-wrens (Malurus, Clytomyias). Our study shows that ILS is common at the family level in birds yet, despite this, species tree methods converge on broadly similar results for this family.

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The paper presents improved methods and new results on the introduction of formal optimization strategies into the design of offshore structures. The hull design stage is singled out from the overall design process and automated by introducing parametric shape generation, numeric hydrodynamic analysis and assessment tools as well as Nonlinear Programming algorithms for process control. The investigation compares the performance of three different optimization algorithms within a shape optimization framework. The classical deterministic Sequential Quadratic Programming method competes with two so called global optimization algorithms: The popular Genetic Algorithm and the more exotic Adaptive Simulated Annealing. The applications show that significant improvements of seakeeping qualities are obtained in either case. As expected, the global methods require definitely more computation time than the deterministic algorithm. Furthermore the global methods do not always produce better results, which makes a careful choice of the optimization algorithm mandatory. Guidelines for an efficient application are given in the conclusions.

In developing countries, government actively promotes foreign investment in order to adapt the new and latest technology. This leads to greater R&D activities, thus this creates knowledge and technology spillover. In this paper, we look at Korea where the R&D has been the main factor of rapid growth. We study the effects of foreign ownership on technological performance by looking at 756 R&D intensive Korean firms from 1999 to 2009. We look the number of applied and registered patents are dependent variables (as a technological performance) and observe statistically significant and positive correlation with foreign ownership due to three main reasons: (a) knowledge and technology spillover, (b) relatively more risk-taking investment behavior of institutional investors, and (c) cherry-picking strategy of investing in firms that perform well. Furthermore, we also observe the R&D expenditure has a strong and positive correlation with the number of applied and registered patents, and R&D expenditure could serve as a proxy variable for technologically advanced industries. Lastly, we observe that the coefficients increase for applied and registered patents for different technology index sub-groups.