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The assessment of station designs by applying pedestrian flow simulation models is addressed. In particular, station design issues pertain to the way access gates will affect pedestrian flow operations in regard to levels of service, congestion levels, average walking times, delays incurred at gates, and so forth. Effects of different system layouts are studied, as well as the difference between different gate systems (low- and high-capacity systems), in regard to processing passenger flows. Finally, pedestrian flow operations in case of emergency situations are of interest. To examine those issues, pedestrian traffic operations for different station design alternatives are predicted with the dynamic microscopic pedestrian flow model NOMAD. That is done for reference situations (validation) as well as for design alternatives. The NOMAD model has been extended with a new module describing pedestrian operations (i.e., user-optimal gate choice) at the gates. It is found that the simple design guidelines used to set up the design alternatives provide a satisfactory level of service to transferring pedestrians and that the gates can be installed without compromising passenger safety. Nevertheless, the need to reroute, inefficient gate use, and interactions between conflicting pedestrian flows cause small but significant delays to transferring pedestrians that cannot have been predicted without the use of an adequate microsimulation model.

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The Selvagens Islands are located in the northeastern Atlantic between the Canary Islands and Madeira Island. As a result of their small size, remote location and harsh sea conditions only a few studies have been conducted to describe their marine species diversity. We were able to identify 29 new coastal fish species, an increase of 33% in the ichthyofauna described for these islands (n = 88). There is a prevalence of species with tropical affinities and only 2.3% (n = 2) are endemic to Macaronesia. Considered a stepping-stone colonization vector from the nearest continental shore, as proposed by other authors for this region, the Selvagens Islands host 34.1% of the ichthyofauna described for the much larger Canary Islands (n species = 258, submerged area n SelvagensIs. = 2.3%) and 47.3% of the ichthyofauna described for the more distantly located Madeira Island (n species = 186, submerged area n SelvagensIs. = 17.9%). Interestingly, 6.8% (n = 6) of the species failed to bridge the gap between the Selvagens Islands and Madeira Island. Data collected so far showed no trend toward an increasing number of species with high dispersal capability. The Selvagens Islands are an example of a high coastal species diversity occurring even in very small areas of the northeastern Atlantic Ocean.

The common dolphinfish (Coryphaena hippurus) is an epipelagic, mid-trophic level, highly migratory species distributed throughout the world’s tropical and subtropical oceans in waters greater than 20°C. Life-history variables, migratory behaviour, and genetic markers have been used to define major stocks in the central Atlantic Ocean and Mediterranean Sea. Here, we used the mitochondrial DNA gene NADH subunit 1 (688 bp) to test for differences between population groups. A total of 103 haplotypes were detected among 203 fish. Gene diversities in samples were large and similar among populations (mean h = 0.932; range 0.894–0.987), but nucleotide diversities varied widely among samples (range π = 0.004–0.034) and appear to reflect population histories. Principal component analysis revealed two large populations groups, and the analysis of molecular variation and pairwise values of ΦST resolved population structure within these groups. Populations in the eastern Atlantic and Mediterranean showed the largest amounts of divergence from one another (ΦCT = 0.331). Adult movement and biophysical barriers to larval dispersal may explain contemporary differences between stocks, but the divergent populations in the Mediterranean Sea are likely due to isolations by cold temperature barriers during Pleistocene glaciations. The geographically large stock groupings require international cooperation in the harvest management and conservation of local dolphinfish populations.

Nowadays, there is a huge need for efficient tools to produce virtual models, mostly urban, in several areas such as architecture, movies, games, virtual worlds and commercial applications. These models may be either generated "fictional" models or reconstructed models representing real world structures. This last option is the motivation behind this paper and past experience has shown us that, usually, it is harder to recreate existing models than trying to create new ones.The purpose of the research here addressed is the deϐinition of a method to efϐiciently produce 3D models of existing buildings. The method allows the 3D creation of buildings' structures (interior and exterior) and corresponding surrounding environments from existing information such as floor plans (in any format), photographs, etc. It also allows the application of different materials (textures and colours) to the buildings' structure and to place and distribute objects logically. The method is established through the development of a software prototype -AV3D (Ambientes Virtuais 3D -3D Virtual Environments) -that allows the production of the realistic results shown in this paper.

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