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The present study described the neuro-anatomy of a larval coral reef fish Amphiprion ocellaris and hypothesized that morphological changes during the transition from the oceanic environment to a reef environment (i.e. recruitment) have the potential to be driven by changes to environmental conditions and associated changes to cognitive requirements. Quantitative comparisons were made of the relative development of three specific brain areas (telencephalon, mesencephalon and cerebellum) between 6 days post-hatch (dph) larvae (oceanic phase) and 11 dph (at reef recruitment). The results showed that 6 dph larvae had at least two larger structures (telencephalon and mesencephalon) than 11 dph larvae, while the size of cerebellum remained identical. These results suggest that the structure and organization of the brain may reflect the cognitive demands at every stage of development. This study initiates analysis of the relationship between behavioural ecology and neuroscience in coral reef fishes.

Background The clownfish Amphiprion ocellaris is one of the rare coral reef fish species that can be reared in aquaria. With relatively short embryonic and larval development, it could be used as a model species to study the impact of global changes such as temperature rise or anthropogenic threats (eg, pollution) on the postembryonic development at molecular and endocrinological levels. Establishing a developmental table allows us to standardize sampling for the scientific community willing to conduct experiments on this species on different areas: ecology, evolution, and developmental biology. Results Here, we describe the postembryonic developmental stages for the clownfish A. ocellaris from hatching to juvenile stages (30 days posthatching). We quantitatively followed the postembryonic growth and described qualitative traits: head, paired and unpaired fins, notochord flexion, and pigmentation changes. The occurrence of these changes over time allowed us to define seven stages, for which we provide precise descriptions. Conclusions Our work gives an easy system to determine A. ocellaris postembryonic stages allowing, thus, to develop this species as a model species for coral reef fishes. In light of global warming, the access to the full postembryonic development stages of coral reef fish is important to determine stressors that can affect such processes., Key Findings Seven developmental stages have been identified to describe the larval development of the clownfish Amphiprion ocellaris.Clownfish larvae undergo two distinct developmental growth phases that correspond to growth and metamorphosis.A dichotomous key determination has been created to assist users in identifying the various developmental stages.

Resume : L'elaboration des Eurocodes, normes europeennes sur le calcul des constructions, a ete menee depuis les annees 80. Ils sont bases sur les methodes semi-probabilistes qui introduisent des coefficients partiels. Actuellement, peu de logiciels sont capables de prendre en compte cette approche semi-probabiliste. Ils doivent s'adapter pour repondre aux enjeux et criteres des nouvelles normes europeennes. Partant du constat que peu de logiciels permettent le calcul semi-probabiliste des Ducs d'Albe, le CETMEF a decide de developper un logiciel : Fudaa-Albe (CETMEF, site web). Ce logiciel est base sur l'utilisation du logiciel Albe developpe dans les annees 80 par le CETMEF, permettant le dimensionnement par analyse elasto-plastique des Ducs d'Albe avec une approche globale. Ce logiciel a ete modifie pour integrer une approche semi-probabiliste et complete par l'utilisation d'une nouvelle interface de calcul: Fudaa qui facilite son utilisation (logiciel autrefois developpe sous DOS). Les defenses d'accostage et le calcul d’energie d’accostage sont integres en donnees d'entree du logiciel et donc pris en compte dans le calcul pour faciliter le travail du concepteur.

First uses of ROSA 2000 showed that bad adaptation to semi-probabilistic format of present calculation tools complicates the limit-states verification of structures. A study made the inventory of the existing commercial softwares and evaluated their compatibility with the use of semi-probabilistic methods. 154 softwares were inventoried. The study of the softwares showed that for a type of structure there are different calculation methods, each country privileges one or several ground investigations and calculation methods. Only 20% of the softwares are adapted to the use of semi-probabilistic methods. In order to facilitate the use of ROSA 2000 several proposals are made for modernizing quickly the existing softwares. Mots-cles : semi-probabiliste / eurocodes / logiciel / coefficient partiel / etat-limite 1.Introduction D’ici la fin de la decennie les Eurocodes deviendront d’application obligatoire dans l’ensemble des pays de l’Union Europeenne (UE). Les Eurocodes utilisent le format de calcul semi-probabiliste avec la mise en œuvre de coefficients partiels de securite. En France comme dans les autres pays de l’UE, l’usage des Eurocodes va entrainer des changements par rapport aux methodes de calcul traditionnelles qui utilisent des coefficients de securite globaux et qui sont utilisees pour de nombreux types d’ouvrages. Afin de preparer la transition entre les reglements actuels et les Eurocodes le CETMEF (Centre d’Etudes Techniques Maritimes et Fluviales) a redige puis diffuse les Recommandations pour le calcul aux etats-limites des Ouvrages en Site Aquatique (ROSA 2000). Realise dans la seconde moitie des annees 1990, ROSA 2000 se base sur les regles de calculs semi-probabilistes deja existantes en France et dans les autres pays de l’UE ainsi que sur les versions d’application volontaire des Eurocodes (ENV). ROSA 2000 a deja ete mis en œuvre sur au moins quatre projets. Les premiers retours d’experience (ecran mixte pieux et palplanches a Dunkerque, quai sur pieux a Honfleur) s’accordent sur 3 points