270 resultados para juvéniles de poissons


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This paper provides data on diet and feeding habits of five benthic fish species (Torpedo torpedo (Linnaeus,1758), Mullus surmuletus (Linnaeus, 1758), Uranoscopus scaber (Linnaeus,1758), Scorpaena scrofa (Linnaeus,1758) and Synaptura lusitanica (Capello,1868)) common in the artisanal fisheries in the Cullera coast (Mediterranean sea – Spain) and T.torpedo, U.scaber y S. lusitánica feeding habits are almost unknown. T. torpedo preferred small preys like fishes, polychaetes and molluscs, these preys were feed in small portions. M. surmuletus showed the highest feeding dynamic, consuming small prey in large numbers like crustaceans (brachyura and amphypoda). U. scaber had similar feeding habits, but the numbers of preys in the stomach were lower. The principal preys were fishes, crustaceans, molluscs and polychaetes. S.scrofa ate larger prey items such as fish, followed by crustaceans and molluscs. Finally S. lusitánica had a high vacuity index, feeding polychaetes as the most important prey in their diet. Feeding strategy indicates a specialization of T.torpedo, S.scrofa and S. lusitanica; conversely M. surmuletus and U. scaber were generalized species.

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European fishery off Mauritania (one of the most productive and most intensively exploited regions in the world) targeted to small pelagic fish accounts for 30% of the total catches in the area. The Instituto Español de Oceanografía (IEO), through its Centro Oceanográfico de Canarias, follows up the activity of these vessels that land at Spanish port (Las Palmas de Gran Canaria, Spain), under the European Project Data Collection (Regulation (EC) 1543/2000). One of the target groups in this fishery is Trachurus spp, commercially named “JAX”. During 2008 and 2009, several samples of this group from these landings were analysed, and Caranx rhonchus was the second species of importance. The mixture of these species in the landings of this UE fleet should be determined to improve the data provided to the international Working Groups responsible for assessment of those resources.

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Background: While research continues into indicators such as preventable and amenable mortality in order to evaluate quality, access, and equity in the healthcare, it is also necessary to continue identifying the areas of greatest risk owing to these causes of death in urban areas of large cities, where a large part of the population is concentrated, in order to carry out specific actions and reduce inequalities in mortality. This study describes inequalities in amenable mortality in relation to socioeconomic status in small urban areas, and analyses their evolution over the course of the periods 1996–99, 2000–2003 and 2004–2007 in three major cities in the Spanish Mediterranean coast (Alicante, Castellón, and Valencia). Methods: All deaths attributed to amenable causes were analysed among non-institutionalised residents in the three cities studied over the course of the study periods. Census tracts for the cities were grouped into 3 socioeconomic status levels, from higher to lower levels of deprivation, using 5 indicators obtained from the 2001 Spanish Population Census. For each city, the relative risks of death were estimated between socioeconomic status levels using Poisson’s Regression models, adjusted for age and study period, and distinguishing between genders. Results: Amenable mortality contributes significantly to general mortality (around 10%, higher among men), having decreased over time in the three cities studied for men and women. In the three cities studied, with a high degree of consistency, it has been seen that the risks of mortality are greater in areas of higher deprivation, and that these excesses have not significantly modified over time. Conclusions: Although amenable mortality decreases over the time period studied, the socioeconomic inequalities observed are maintained in the three cities. Areas have been identified that display excesses in amenable mortality, potentially attributable to differences in the healthcare system, associated with areas of greater deprivation. Action must be taken in these areas of greater inequality in order to reduce the health inequalities detected. The causes behind socioeconomic inequalities in amenable mortality must be studied in depth.

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The effect of foundation embedment on settlement calculation is a widely researched topic in which there is no scientific consensus regarding the magnitude of settlement reduction. In this paper, a non-linear three dimensional Finite Element analysis has been performed with the aim of evaluating the aforementioned effect. For this purpose, 1800 models were run considering different variables, such as the depth and dimensions of the foundation and the Young’s modulus and Poisson’s ratio of the soil. The settlements from models with foundations at surface level and at depth were then compared and the relationship between them established. The statistical analysis of this data allowed two new expressions, with a mean maximum error of 1.80%, for the embedment influence factor of a foundation to be proposed and these to be compared with commonly used corrections. The proposed equations were validated by comparing the settlements calculated with the proposed influence factors and the true settlements measured in several real foundations. From the comprehensive study of all modelled cases, an improved approach, when compared to those proposed by other authors, for the calculation of the true elastic settlements of an embedded foundation is proposed.

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O concreto, de um modo geral, apresenta um bom comportamento em situação de incêndio quando comparado com o aço, todavia em função da temperatura ocorrem algumas transformações químicas e físicas que podem comprometer esse desempenho. Apesar das alterações das propriedades mecânicas e térmicas do concreto quando sujeito a temperaturas elevadas e após situação de incêndio já terem sido avaliadas em vários estudos, ainda é um campo aberto onde é necessário muita investigação. O presente artigo apresenta os resultados de um estudo experimental sobre a avaliação das propriedades mecânicas residuais de concretos normais após incêndio. Para o efeito foram selecionados agregados graníticos e agregados calcários, dado serem os agregados mais utilizados na construção civil em Portugal e em muitos outros países. Os parâmetros testados foram: o nível de carregamento (0,3fcd e 0,7fcd); o processo de arrefecimento (arrefecimento ao ar e arrefecimento por jato de água) e o nível máximo de temperatura atingida (20, 300, 500 e 700ºC). As propriedades mecânicas estudadas foram a resistência à compressão residual, resistência à tração direta e resistência à tração por compressão diametral, resistência à flexão, módulo de elasticidade e coeficiente de Poisson. As temperaturas atingidas e o arrefecimento rápido do concreto apresentaram um efeito negativo sobre as propriedades mecânicas residuais. Este efeito foi mais notório na resistência à compressão residual do que nas restantes propriedades mecânicas estudadas.

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Connaître le sexe d’un oiseau est important pour divers domaines notamment pour les vétérinaires, les écologistes ainsi que pour les éleveurs d’oiseaux qui veulent former des couples qui serviront à la reproduction. Plusieurs espèces d’oiseaux, juvéniles et adultes, n’ont pas de dimorphisme sexuel. L’utilisation de l’ADN est une façon rapide de déterminer le sexe à partir d’un échantillon de sang, de muscle, de plumes ou de fèces. Par contre, la méthode devrait être validée pour chaque espèce et idéalement, standardisée. Le premier objectif de cette étude est de développer une méthode de sexage par séquençage des oiseaux à partir des séquences du gène CHD, en utilisant les oiseaux de proie et les perroquets vus en clinique au Québec. Un deuxième objectif est de faire l’identification de l’espèce à sexer, à partir du gène mitochondrial COX-1 et aussi à partir des séquences CHD-Z et CHD-W, utilisés pour le sexage. Un troisième objectif est d’évaluer les séquences sorties (CHD-Z, CHD-W et COX-1) en vue d’une étude phylogénique. Une extraction d’ADN a été effectuée chez 27 espèces de perroquets, 34 espèces d’oiseaux de proie, une corneille (Corvus brachyrhynchos) et un poulet (Gallus gallus). Une amplification par PCR a été exécutée pour les exons partiels 23 et 24 du gène CHD. Le séquençage de cet amplicon permettait de savoir s’il s’agissait d’un mâle (séquence simple CHD-Z) ou d’une femelle (séquences CHD-Z et CHD-W qui se chevauchent). Afin d’avoir des séquences CHD-W distinctes, un sous-clonage a été fait chez les femelles de chaque espèce. De cette manière, les séquences partielles du gène CHD, Z et W, ont été trouvées pour les espèces échantillonnées. Une étude phylogénique a été effectuée avec les séquences de COX-1, CHD-Z et CHD-W grâce au site « Clustal-Omega ». La méthode de sexage des oiseaux par séquençage du gène CHD est standard et efficace. Le gène COX-1 permet une meilleure identification des espèces parentes et le gène CHD-Z est le plus utile pour étudier la phylogénie profonde.

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Subtitle of 2e série: pour piano seul.

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Accompanied by "Suite éditée aux frais du Barrande fonds. Problematica silurica. Publiés par le Prof. Dr. Anton Fritsch. Avec 12 planches. Traduit par A. S. Oudin, ... " (28 p. illus., 12 pl. 33 cm.) Published: Prague, Leipzig, R. Gerhard, 1908.

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[v. 2] Quadrumanes.--[v. 3] Reptiles et poissons, avec la collaboration de m. E. Desmarest.--[v. 5-7] Coléoptères, avec la collaboration de m. E. Desmarest.--[v. 8] Annelés.--[v. 9] Papillons.--[v. 10] Papillons nocturnes, avec la collaboration de m. E. Desmarest.

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T. 1: Histoire naturelle des animaux (Contiene : Introduction a l'histoire naturelle par. M. Daubenton; Les animaux quadrupedes et les cetaces ; Ornitologie, par M. Mauduyt ; Discours genaraux sur la nature des oiseaux [y la primera parte del Dictionnaire d'Ornithologie] (viii, lxxxxii, 691 p., [1] en bl.) -- T. 2: Oiseaux (Contiene : Dictionnaire d'ornithologie; Les animaux quadrupedes, ovipares, et les serpents par M. Daubenton ([4], 712 p.) -- T. 3: Les poissons ([4], lx, 435 p., [1] en bl.) -- T. 4-8: Insectes / par M. Olivier ([4], ccclxxiij, [3] en bl., 331, [1] en bl. ; [4], 793, [1] en bl. ; [4], 704 ; [4], 827, [1] en bl. ; [4], 722 p.; contiene tambien "Discours préliminaire et plan du dictionnaire des insectes / par M. Mauduyt" (cclxxxviii p.)) -- T. 9-10: Entomologie, ou histoire naturelle des crustaces, des arachnides et des insectes / par M. Latreille ... et m. Godart ; [Le Peletier de Saint-Fargeau, Serville et Guerin] ([4], 828 ; [6], 832, [2] p.)