Browsing by Issue Date, starting with "2006-04"
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- Molecular characterization of the "Cottonii" form of fucus in the North-Eastern Pacific versus the AtlanticPublication . Serrão, Ester; Vliet, M. S.; Hansen, G. I.; Maggs, C. A.; Pearson, G. A.Along the west coast of North America, three species of Fucus are reported to occur: F. gardneri Silva, F. spiralis Linnaeus, and the controversial F. cottonii Wynne & Magne. Our study investigates the identity of F. cottonii in this area and compares it with isolates from the NortheasternAtlantic. The thalli from both areas vegetatively resemble one another, lacking midribs, and they occur in similar salt marsh habitats.
- Performance as a classification criterion of tourist origins and destinationsPublication . Águas, Paulo; Rita, Paulo; Costa, JorgeThe definition of performance variables, which can be used as indicators of the results obtained/to be obtained, is a fundamental prerequisite in the carrying out of any evaluation process. Portfolio analysis has been used as a tool for the study of market segments, namely of tourist destinations. However, a review of the literature did not identify a single case where the performance variable is adjusted to the nature of the object. In fact, contrary to many other situations, the use of performance variables in absolute terms does not appear to be the most recommendable solution given that the total volume is conditioned by the size of the territory and, above all, by the number of inhabitants. In other words, for a certain level of socio-economic development, larger countries (in terms of size and number of inhabitants) will tend to have higher absolute values. Besides this, the empirical studies reviewed contain little, or no, information about competition, being temporally static. Although in some cases growth rate is used as a variable, thus presupposing the consideration of two magnitudes in two different moments in time, more than one register per object is never considered, meaning that evolutive analyses are not viable. Consequently, a performance proxy was developed which enables a direct comparison between generating countries (origins) and between destinations, regardless of the number of inhabitants. The selection of the performance proxy can depend on the object of study. In any case, it should always permit the evaluation, in general terms, of the results obtained by the destination for the set of origins under analysis and the results generated by the origin for the set of destinations under study. The proposed tool is a component of a model for the identification of priority market segments, and is constituted by a system of orthogonal axes which produces four quadrants that are distinct in terms of intensity (axis OY) and growth (axis OX) of tourist flows. The tool, like the model, can be applied to any type of destination (city, region or country) and to any market segmentation criterion (geographic, demographic, behavioural, psychographic or other). In the study reported here, the instrument is applied to the 15 Member States of the European Union (before its expansion on May 1st 2004), for the period from 1996 to 2001. Eurostat was the sole source of data for the study. The UK and Ireland are the countries classified as ‘Progressing Origins’. With 16.8% of the population, they increased their contribution from 17.7% to 21.9% and are responsible for 38.7% of the growth that occurred between 1996 and 2001. Spain, Greece and Ireland are the countries classified as ‘Progressing Destinations’. With 14.4% of the population, they increased their share of the market from 21.5% to 24.2%, capturing 35.1% of the growth that occurred between 1996 and 2001.
- A genetic linkage map of the hermaphrodite teleost fish Sparus aurata L.Publication . Franch, Rafaella; Louro, Bruno; Tsalavouta, Matina; Chatziplis, Dimitris; Tsigenopoulos, C.; Sarropoulou, Elena; Antonello, Jenny; Magoulas, Andonis; Mylonas, Constantinos C.; Babbucci, Massimiliano; Patarnello, T.; Power, Deborah; Kotoulas, Georgios; Bargelloni, LucaThe gilthead sea bream (Sparus aurata L.) is a marine fish of great importance for fisheries and aquaculture. It has also a peculiar sex-determination system, being a protandrous hermaphrodite. Here we report the construction of a first-generation genetic linkage map for S. aurata, based on 204 microsatellite markers. Twenty-six linkage groups (LG) were found. The total map length was 1241.9 cM. The ratio between sex-specific map lengths was 1:1.2 (male:female). Comparison with a preliminary radiation hybrid (RH) map reveals a good concordance, as all markers located in a single LG are located in a single RH group, except for Ad-25 and CId-31. Comparison with the Tetraodon nigroviridis genome revealed a considerable number of evolutionary conserved regions (ECRs) between the two species. The mean size of ECRs was 182 bp (sequence identity 60–90%). Forty-one ECRs have a known chromosomal location in the pufferfish genome. Despite the limited number of anchoring points, significant syntenic relationships were found. The linkage map presented here provides a robust comparative framework for QTL analysis in S. aurata and is a step toward the identification of genetic loci involved both in the determination of economically important traits and in the individual timing of sex reversal.