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Background: The objective of this study was to determine the prevalence of radiolucent lines (RLLs) around the femoral component in a cohort of patients who underwent well-functioning cementless total hip arthroplasty (THA). Methods: A cohort of unrevised Corail (DePuy Synthes, Raynham, MA) femoral components (n = 636) were analyzed at a median follow-up of 6.0 years (interquartile range: 5.2-6.8) with the Oxford Hip Score (OHS) and radiographs. Two independent observers assessed the radiographs for the presence of RLLs. Results: The overall prevalence of RLLs in zone 7 was 13% (83/636). Patients with RLLs in zone 7 had an average OHS of 40.3 (15-48), and those who did not have RLLs in zone 7 had an average OHS of 38 (6-48), P = .07. Both groups had an average pain score of 1.6 out of 5, P = .5. The prevalence of RLLs in zone 7 was much less in the collared femoral components (2.6% prevalence) than in the collarless components (23.6% prevalence), but there was heterogeneity between these 2 groups preventing comparison. Logistic regression analysis of only the collarless components identified undersizing as the only predictive (odds ratio = 2.6) factor for RLL development in zone 7. Conclusions: Undersizing the Corail stem is strongly predictive of developing RLLs in zone 7. Preoperative templating for the appropriate size is critical. We observed more RLLs in zone 7 with the collarless design Corail, but a comparison study with the same bearing couple is needed to investigate this further. Keywords: Hip, Uncemented, Cementless, Templating, Collar, Corail

International audience

A number of archaeological salvage excavations conducted in Alexandria (Lower Egypt) by the Centre d'Etudes alexandrines have provided a corpus of around 2000 fragments of marine, freshwater and terrestrial invertebrates. These archeomalacological remains come from several occupation layers of the same district within the town, the Brucheion, dating from the end of the 4th century BC until the 6th century AD. After macroscopic observations and through a binocular microscope, the analysis of the malacofauna vestiges has provided previously unknown information regarding the exploitation of the aquatic environment by Alexandrians during antiquity. In addition, some residues of mineral material preserved on the shells have been analysed under a scanning electron microscope (SEM). This study sheds light on both consumption choices and on the variety of uses for shells (container, decoration, raw material) within the Alexandrian domestic context. Certain species from the Red Sea and the Western Mediterranean Sea provide new data on the movement of products of marine origin within Ptolemaic and Roman Egypt.

Dictionnaire de la Méditerranée, sous la direction de Dionigi Albera, Maryline Crivello et Mohamed Tozy, en collaboration avec Gisèle Seimandi, Actes Sud, 2016, 1694 p., ISBN 978-2-330-06466-2., Imprimés, Dicomed-042, DicoMed : Dictionnaire de la Méditerranée

International audience; In the present era of rapid global change, innovative monitoring methods can greatly enhance our ability to detect ecological disturbances and prioritise conservation areas in a timely and cost-effective manner. While Passive Acoustic Monitoring (PAM) has recently emerged as a promising tool for monitoring ecological states in marine environments, the specifics of how to apply this method remains poorly defined. In this study we examined how different combinations of sampling settings (frequency bandwidth, time of sampling (day/night), and sample duration) influenced the ability of two acoustic indices, the Sound Pressure Level (SPL) and the Acoustic Complexity Index (ACI), to discriminate different ecological states (ecostates) of coral reefs. We applied an iterative approach to select the most efficient and consistent combinations of sampling settings to use for these two acoustic indices, depending on the stability of their discriminating power across different time scales (successive days, moon phases, and seasons), and the minimum sampling effort required for reliable ecostate assessment. The ability of SPL and ACI to discriminate ecostate-specific soundscapes was more stable and required less sampling effort at nighttime. For indices calculated in the higher frequency band (> 2 kHz), very short recording times (≤20 min divided into 5 s samples) were sufficient to discriminate ecostates, whereas longer recording times (≥200 min divided into 5 min samples) were necessary when using indices calculated in the lower frequency bands (< 1 kHz). An optimised sampling scheme, i.e. the group of the five best combinations of settings to discern among coral reef ecostates, was determined at Reunion Island, Indian Ocean, then tested at New Caledonia, Pacific Ocean. Here, the classifications obtained through visual surveys and with the optimised acoustic sampling scheme were congruent. The concordance of our results with visual fish counts confirms the potential of ecoacoustics to rapidly and reliably characterise coral reefs' ecostate, allowing managers to prioritise conservation areas among numerous sites, and detect ecological changes over time. Our study provides clear guidelines for monitoring soundscapes by means of the ecoacoustic indices most widely used in the marine realm.

International audience; By focusing on several sales of Mediterranean red coral beads that the Marseilles merchant François Garnier and his commission agent François Tiran made in Smyrna around 1680, this paper brings an insight into Eurasian trade during the early modern period, and the variety of links and means that were employed to circulate the goods involved. Moreover, it helped us understand the specific mechanisms of commercial activity in the main Levant port towards the end of the 17 th century and to identify the roles and actions of the men in charge of this trade. Using Smyrna as a 'laboratory', this research focused on the exportation of Mediterranean red coral to Asia, thus giving us a deeper understanding of the traders' practices and intricate workings of exchange, but more specifically on the work of the Marseilles and Armenian traders in a difficult commercial niche, which in fact generated good profits when the products were of high quality and the market had been well-studied.; L’analyse de quelques ventes de grains de corail rouge de Méditerranée du marchand marseillais François Garnier et de son commissionnaire François Tiran à Smyrne autour de l’année 1680 permet d’entrevoir la variété des maillons et des moyens de la circulation des marchandises dans le commerce eurasiatique de l’époque moderne. Elle donne également la possibilité de saisir les ressorts précis de l’activité commerciale dans la principale échelle levantine du XVIIe siècle finissant et de cerner les capacités d’action des hommes qui en ont la charge. À travers le laboratoire smyrniote et une immersion dans la filière d’exportation du corail vers l’Asie, cette recherche a pour objectif d’approcher au plus près les acteurs du négoce, d’examiner leurs pratiques marchandes et les rouages complexes de l’échange. Cette contribution se penche notamment sur le travail des négociants marseillais et arméniens dans une niche commerciale difficile, mais apportant de confortables bénéfices quand les produits sont de qualité et les caractéristiques du marché bien analysées.

Tropical reef-building corals are at the basis of extremely biodiverse ecosystems on which many species depend, including human beings. Today, climate change represents a threat for the future survival of corals, and it is becoming crucial to better understand the physiology of these key species and the mechanisms underlying their responses to environmental change. The work conducted during my PhD focused on the characterization of the processes affected by temperature changes in Stylophora pistillata. For this purpose, I used multiple approaches from the animal to the gene. My results showed that: 1) calcification, photosynthesis and respiration declined drastically at the extremes of the thermal performance window, 2) light-enhanced calcification occurs across the thermal performance window except at low temperature, 3) a group of genes involved in inorganic carbon transport is under-expressed when calcification is reduced (thermal stress and during night), 4) pH in the extracellular calcifying medium remains stable at low and high temperatures, 5) paracellular permeability is highest when calcification increases (25°C and during the day). Information gained from this lab-based study will be useful in guiding further research in the field in order to evaluate coral health and predict the future of coral reefs in a changing world., Les coraux tropicaux constructeurs de récifs sont à l’origine d’écosystèmes extrêmement riches dont dépendent de nombreuses espèces, y compris l’Homme. Aujourd’hui, les changements climatiques représentent toutefois une menace pour la survie des coraux. Afin de comprendre la réponse de ces espèces aux modifications environnementales, il est essentiel d’avoir des informations sur la physiologie de ces espèces-clé. Les travaux conduits au cours de ma thèse ont ainsi permis de caractériser, au niveau mécanistique, les processus affectés par des changements de température chez l’espèce Stylophora pistillata. Pour cela, j’ai employé des approches multiples en partant de l’animal jusqu’au gène. Mes résultats ont montré : 1) que les taux de calcification, de photosynthèse et de respiration sont drastiquement réduits aux extrémités de la fenêtre thermique, 2) l’existence d’un phénomène de « light-enhanced calcification », excepté à basse température, 3) la sous-expression d’un groupe de gènes impliqué dans le transport du carbone inorganique lorsque les taux de calcification sont réduits (stress thermiques et la nuit), 4) la stabilité du pH dans le milieu extracellulaire calcifiant dans tous les traitements, et 5) l’augmentation de la perméabilité paracellulaire conjointement à l’augmentation de la calcification (25°C et le jour). En plus de leur intérêt en recherche fondamentale, ces informations peuvent constituer des outils utiles pour de futures recherches sur le terrain dans le but d’évaluer l’état de santé des coraux et prédire leur devenir dans un monde qui change.

International audience; The critically endangered coral species Acropora palmata used to dominate shallow Caribbean reefs but since the early 1980s, populations have dramatically declined. At the Caribbean scale, A. palmata is divided into two genetically divergent lineages and most of previous works investigating population connectivity among populations involved the western line-age (in Florida, the Bahamas, the Mesoamerican Reef System, and the Greater Antilles). Small scale genetic connectivity among A. palmata populations was globally found, possibly enhancing populations' recovery at the local scale. Yet, little is known regarding the genetic connectivity of populations of the eastern lineage, especially those of the Lesser Antilles, a fragmented archipelago located at the edge of the species distribution. Here, we filled this gap by investigating the genetic diversity, population structure and connectivity of A. palmata populations among 36 sampled sites from 11 islands of the Lesser Antilles using 14 hypervariable microsatellite loci. Globally, genetic diversity levels in A. palmata populations from the Lesser Antilles were lower compared to what was previously reported within the Wider Caribbean. The analysis of the genetic structure, crossed with spatial autocorrelation analysis, revealed an isolation-by-distance pattern at both reef and Lesser Antilles scales. A gene dispersal distance of less than a kilometer, and a northward gene flow direction, in agreement with ocean surface currents in the region were found. Altogether, our results suggest a restricted population connectivity and short distance dispersal of A. palmata larvae within the Lesser Antilles further limited by geographic distances among suitable habitat patches. Additionally, our results suggest that southernmost populations are potential sources of larvae for the most northerly islands and have a key role in reseeding A. palmata populations of the Lesser Antilles.

International audience; Environmental conditions are known to influence corals and their associated communities of microorganisms. However, our insights into the impacts of seasonal changes in ultraviolet radiation (UVR) on both coral physiology and microbiome remain very limited. To address this challenge, we maintained the coral Acropora muricata shaded from UVR or under ambient UVR levels during two contrasting seasons, i.e. summer and winter, and assessed the impact of UVR on the coral holobiont at each season. To this end, we analyzed the physiology (e.g., calcification, protein content, photosynthesis-related parameters) and coral microbiota composition, as well as the abundance and composition of the microbial communities and organic matter contents of the surrounding seawater. Our results show major seasonal effects on coral phenotype: (1) a lower host biomass and photosynthesizing, but fast calcifying phenotype in summer, and (2) a higher host biomass and photosynthesizing, but slow calcifying phenotype in winter. UVR had only a significant impact on Symbiodinium functioning. Specifically, high UVR levels reduced photosynthesis efficiency in summer, but an increase in chlorophyll a content may have compensated for this effect. The coral microbiota, which was variable but generally dominated by Endozoicomonas, was not affected by UVR, but its composition differed between seasons. In contrast, UVR had a major, but differential impact on the seawater microbial communities at both seasons. Particularly in summer, bacteria from the Alteromonadaceae were significantly more abundant (15-fold; up to 75%) in seawater under ambient UVR levels. Overall, our study suggests that UVR has only a limited impact on coral holobiont composition and functioning, despite major fluctuations in the surrounding seawater microbiome; seasonal changes in the holobiont are thus mostly driven by other environmental factors.

International audience; In the eighteenth century, European observers highlighted the passion of the people of black Africa for Mediterranean red coral. This product appeared in the cargoes of European slave ships either in the form of branches or in polished form and became part of the first globalization of commerce. It was especially important in trade between Europe and Asia. Marseille contributed to these exchanges thanks to nearby coral reefs and the French Royal Company of Africa’s control of those in North Africa. The coral was then cut and polished in workshops and factories around the city. It accounted for a small portion of the merchandise boarded on Marseilles ships engaged in the Atlantic slave trade. Traders also served as links between the French Royal Company of Africa and the East India Company (Lorient) to disseminate part of the Mediterranean production. Coral was used to buy slaves but also as a “product appeal” to begin a negotiation.; Au xviiie siècle des observateurs soulignent la passion des populations d’Afrique noire pour le corail rouge de Méditerranée. En branche ou travaillé, ce produit figure dans les cargaisons des navires négriers européens. Très tôt contrôlé par des marchands et de puissantes compagnies, le corail participe à la première mondialisation des échanges. Il prend une place originale dans l’intensification des relations avec l’Asie. Marseille contribue à ces échanges à partir de ressources locales ou exploitées dans les concessions d’Afrique du Nord par la Compagnie royale d’Afrique. Le corail est transformé dans de proches ateliers et manufactures. Il compose une petite partie des marchandises de navires marseillais qui se livrent à la traite négrière. Des négociants servent aussi de liens entre la Compagnie royale d’Afrique et la Compagnie des Indes orientales (Lorient) pour diffuser une part de la production méditerranéenne. Le corail sert à des achats d’esclaves mais aussi de <> pour amorcer une négociation.

International audience; Parmi les ressources de la mer, le corail rouge ‑ Corallium rubrum ‑ occupe dans les activités maritimes de Marseille une place discrète malgré une présence attestée sur la très longue durée. Dans une histoire complexe de la production et des usages de ce produit, le xviie siècle constitue une sorte d’apogée pour sa transformation tandis que le xviiie semble davantage un temps de repli sinon de déclin. Aussi, l’ouverture en 1781 d’une manufacture de corail par Joseph Miraillet et Jacques-Vincent Rémuzat, deux entrepreneurs issus de grandes familles négociantes de la place, appara\ⁱt comme une tentative pour relancer une industrie marseillaise déprimée. Cet établissement n’a toutefois qu’une brève activité dans la mesure où la tourmente révolutionnaire met fin à son existence en 1792. Pourtant, malgré ce cadre doublement limitée – une entreprise, une décennie ‑ l’étude de la société Miraillet, Rémuzat & Cie fournit des éclairages intéressants sur ce secteur d’activité à la fin du xviiie siècle.

International audience; Archeological material and the archival sources provide an insight into the way coral was integrated into the medieval economy in Provence. Toll fees and notarial deeds document the entry areas of coral in Provence as well as the circulation of this raw material and end-products. The analysis of the refusal of production found in Marseille provides first hypotheses of the coral craftwork. These are used in jewelry for the manufacture of pearls and pendants for producing knife handles, ear picks, and whistles. When powdered, coral also becomes an ingredient of pharmaceutical preparations for taking care of one’s body and teeth.; Les découvertes archéologiques et le dépouillement des sources d’archives donnent un aperçu de la manière dont le corail s’insère dans l’économie médiévale en Provence. L’association des tarifs de péage et des archives notariales documente les zones d’entrée du corail en Provence occidentale ainsi que la circulation de cette matière à l’état brut ou sous forme travaillée. L’analyse des déchets retrouvés à Marseille apporte de premières hypothèses sur les étapes initiales de transformation des branches. Celles-ci sont employées en bijouterie pour la fabrication de perles et de pendentifs, servent ponctuellement à l’élaboration de manches de couteaux, de cure-oreilles et de sifflets. Mis en poudre, le corail devient aussi un ingrédient de préparations pharmaceutiques, pour le soin du corps et des dents.

International audience; Classé dans l’embranchement des cnidaires et formant des colonies soutenues par un squelette axial calcaire, le corail rouge de Méditerranée (Corallium rubrum, Linnaeus 1758) est une espèce dont la nature animale a été révélée par le médecin marseillais Jean André Peyssonnel au cours des années 1720, puis acceptée par la communauté scientifique internationale après un rapport d’Antoine de Jussieu en 1742. Si Corallium rubrum est parfois présent sur les côtes européennes et africaines de l’océan Atlantique, notamment au Maroc et au Portugal, ses principaux gisements sont concentrés dans le bassin occidental de la Méditerranée, sur les rivages de la frontière algéro-tunisienne et sur les côtes rocheuses qui s’étendent du détroit de Gibraltar à celui de Messine (Costa Brava, Provence, Corse, Sardaigne, Sicile, Ligurie, Toscane, Campanie…). À ce titre, et sans trop travestir la réalité, il peut être perçu comme une espèce quasi endémique à l’espace méditerranéen.(...)

Ce texte présente un premier tableau de l’évolution des techniques de la pêche du corail en Méditerranée de la Renaissance à la fin du XIXe siècle. Il s’agit tout d’abord de montrer en quoi les caractéristiques naturelles de l’espèce Corallium rubrum et la pression de la demande ont toujours pesé sur les techniques de pêche. Les permanences et les changements sont observés à la croisée de la spécificité du milieu d’exploitation, de la fluctuation des marchés et des rapports entre pêche, sciences et techniques. Dans le même temps, cette recherche s’attache à saisir l’impact de l’invention et de l’innovation technique sur le métier de corailleur et ses changements dans la longue durée, depuis le règne de la croix de Saint-André jusqu’à la conquête des fonds marins par l’utilisation du scaphandre. Elle décrit une pratique perdant sa singularité et s’articulant de plus en plus avec d’autres activités marines. Par les caractères qui lui sont propres et les éléments qu’elle partage avec les pêches d’autres espèces, la collecte du corail offre des éléments de réflexion pour mieux comprendre des modalités du changement technique dans le domaine halieutique en Méditerranée et appréhender concrètement la tension entre les profits tirés de l’exploitation et la gestion des ressources maritimes.

In the context of global warming, coral reefs are experiencing thermal stresses which are becoming more frequent and intense. In order to get a better understanding of the mechanisms of coral thermo­tolerance, I developed an integrative approach on the coral holobiont (meta­ organism composed of the coral host, its symbiotic algae and microbiota). For this, I performed an ecologically realistic thermal stress experiment on a coral species, Pocillopora damicornis. This species is widespread in the Indo­Pacific area. I compared the response of two populations whose thermotolerance is different since they are subjected to contrasting thermal regimes. I analyzed, for each of them, the response of the coral host (by RNAseq), as well as the structure and changes in the algal and bacterial microbiota (by metabarcoding). The results show that,while the structure of the microbiota is not influenced by stress, coral responds very differently depending on the population studied. The population from a more fluctuating environment displays a more effective and more plastic response, probably thanks to the involvement of epigenetic mechanisms. Another study carried out on different populations of P. damicornisshowed that the composition of the microbiota is influenced by the host genome and the thermal regime. One of the clades of the symbiotic algae, known to improve the heat­tolerance of the coral host, appears more sensitive to low temperatures than the others.; Dans le contexte du réchauffement climatique, les récifs coralliens subissent des stress thermiques de plus en plus fréquents et intenses. Dans le but de mieux comprendre les mécanismes de la thermo­tolérance des coraux, j’ai développé une approche intégrative sur l’holobionte corallien (méta­organisme composé de l’hôte corallien, son algue symbiotique etson microbiote). Pour cela, j’ai réalisé une expérience de stress thermique écologiquement réaliste sur une espèce de corail, Pocillopora damicornis. Cette espèce étant présente dans l’ensemble de l’Indo­Pacifique, j’ai pu comparer la réponse de deux populations dont la thermotolérance est différente puisqu’elles sont soumises à des régimes thermiques contrastés. J’ai analysé, pour chacune d’entre­elles, la réponse de l’hôte corallien (par RNAseq), ainsi que la structure et les changements au niveau des microbiotes algaux et bactériens (par métabarcoding). Les résultats obtenus montrent qu’alors que la structure du microbiote n’est pas influencée par le stress, le corail y répond de façon très différente selon la population étudiée. La population issue d’un environnement plus fluctuant met en place une réponse plus efficace et plus plastique, probablement grâce à l’intervention de mécanismes épigénétiques. Une autre étude réalisée sur différentes populations de P. damicornis dans le cadre de cette thèse montre que la composition du microbiote est influencée par le génome de l’hôte ainsi que par le régime thermique. Un des clades de l’algue symbiotique connu pour améliorer la thermo­ tolérance de l’hôte corallien semble plus sensible aux basses températures que les autres.

In the context of global warming, coral reefs are experiencing thermal stresses which are becoming more frequent and intense. In order to get a better understanding of the mechanisms of coral thermo­tolerance, I developed an integrative approach on the coral holobiont (meta­ organism composed of the coral host, its symbiotic algae and microbiota). For this, I performed an ecologically realistic thermal stress experiment on a coral species, Pocillopora damicornis. This species is widespread in the Indo­Pacific area. I compared the response of two populations whose thermotolerance is different since they are subjected to contrasting thermal regimes. I analyzed, for each of them, the response of the coral host (by RNAseq), as well as the structure and changes in the algal and bacterial microbiota (by metabarcoding). The results show that,while the structure of the microbiota is not influenced by stress, coral responds very differently depending on the population studied. The population from a more fluctuating environment displays a more effective and more plastic response, probably thanks to the involvement of epigenetic mechanisms. Another study carried out on different populations of P. damicornisshowed that the composition of the microbiota is influenced by the host genome and the thermal regime. One of the clades of the symbiotic algae, known to improve the heat­tolerance of the coral host, appears more sensitive to low temperatures than the others.; Dans le contexte du réchauffement climatique, les récifs coralliens subissent des stress thermiques de plus en plus fréquents et intenses. Dans le but de mieux comprendre les mécanismes de la thermo­tolérance des coraux, j’ai développé une approche intégrative sur l’holobionte corallien (méta­organisme composé de l’hôte corallien, son algue symbiotique etson microbiote). Pour cela, j’ai réalisé une expérience de stress thermique écologiquement réaliste sur une espèce de corail, Pocillopora damicornis. Cette espèce étant présente dans l’ensemble de l’Indo­Pacifique, j’ai pu comparer la réponse de deux populations dont la thermotolérance est différente puisqu’elles sont soumises à des régimes thermiques contrastés. J’ai analysé, pour chacune d’entre­elles, la réponse de l’hôte corallien (par RNAseq), ainsi que la structure et les changements au niveau des microbiotes algaux et bactériens (par métabarcoding). Les résultats obtenus montrent qu’alors que la structure du microbiote n’est pas influencée par le stress, le corail y répond de façon très différente selon la population étudiée. La population issue d’un environnement plus fluctuant met en place une réponse plus efficace et plus plastique, probablement grâce à l’intervention de mécanismes épigénétiques. Une autre étude réalisée sur différentes populations de P. damicornis dans le cadre de cette thèse montre que la composition du microbiote est influencée par le génome de l’hôte ainsi que par le régime thermique. Un des clades de l’algue symbiotique connu pour améliorer la thermo­ tolérance de l’hôte corallien semble plus sensible aux basses températures que les autres.

A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp.n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined.

International audience; Global warming is leading to both increases in frequency and intensity of tropical storms, with consequent salinity decrease at shallow reef areas, but also to mass bleaching events and mortality of reef-building corals around the world. Tropical storms can help reef-building corals to reproduce through fragmentation, allowing their expansion throughout the reefs. The combination of high temperature and low salinity may aggravate the effects of coral bleaching. Investigation of alterations at the cellular level will be useful since this is the first detectable response of organisms to changes in environmental conditions. In this study, the long-term oxidative stress induced by elevated temperature (30 °C), low salinity (20 psu), and their combination was studied on fragments of reef-forming corals, and compared to control conditions (26 °C, 33 psu). Determination of oxidative stress biomarkers: lipid peroxidation (LPO); superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) activities in a long-term experiment (60 days), using nine Indo-Pacific reef-forming coral species, provided useful information that was interpreted in combination with the observed general condition of these organisms (appearance: normal, pale, bleached, dead). High temperature affected the general condition of the species tested to a lower degree than did low salinity. Only two species died at high temperature, while low salinity resulted in the death of all species with the exception of two (P. contigua and G. fascicularis). Oxidative damage was detected in some species, as were antioxidant responses, at high temperature. Coral general condition was severely affected in all species in the low salinity treatment. Galaxea fascicularis and Psammocora contigua were the most resistant to salinity stress, having survived the experimental treatment. Oxidative damage was not detected in these species, but there was an antioxidant response. The high temperature + low salinity (HT + LS) treatment had synergistic effects in the condition of all species. Galaxea fascicularis was the only survivor in the HT + LS treatment. Mortality was high (60%) for this species, oxidative damage was not detected, but an increase in SOD activity revealed an antioxidant response.

Thermal stress affects organism performance differently depending on the ambient temperature to which they are acclimatized, which varies along latitudinal gradients. This study investigated whether differences in physiological responses to temperature are consistent with regional differences in temperature regimes for the stony coral Oculina patagonica. To resolve this question we experimentally assessed how colonies originating from four different locations characterized by >3°C variation in mean maximum annual temperature responded to warming from 20 to 32°C. We assessed plasticity in symbiont identity, density, and photosynthetic properties, together with changes in host tissue biomass. Results show that, without changes in the type of symbiont hosted by coral colonies, O. patagonica has limited capacity to acclimatize to future warming. We found little evidence of variation in overall thermal tolerance, or in thermal optima, in response to spatial variation in ambient temperature. Given that the invader O. patagonica is a relatively new member of the Mediterranean coral fauna our results also suggest that coral populations may need to remain isolated for a long period of time for thermal adaptation to potentially take place. Our study indicates that for O. patagonica, mortality associated with thermal stress manifests primarily through tissue breakdown under moderate but prolonged warming (which does not impair symbiont photosynthesis and, therefore, does not lead to bleaching). Consequently, projected global warming is likely to causes repeat incidents of partial and whole colony mortality and might drive a gradual range contraction of Mediterranean corals. This study was partially funded by the Journal of Experimental Biology Travelling fellowship (RR-M), by the Centre Scientifique de Monaco, and James Cook University (MH). The work contributes to the EU project: ‘Mediterranean Sea Acidification under a changing climate’ (MedSeA; grant agreement 265103).

In the current context of global change and the associated need to provide forecasts on the future evolution of the climate as precise as possible, it is crucial to have a deep understanding of the earth climate system. Pacific Ocean is an important compartment of this system. It is the place of strong ocean-atmosphere interactions and the birthplace of the El Niño Southern Oscillation (ENSO), the impacts of which are catastrophic for the environments and the populations. The current knowledge on ENSO partly relies on observations which are however limited in time. To increase this dataset and understand the natural climate variability, additional data are acquired for past periods, based on various type of archives. Because ENSO occurrences are connected with the seasonal variability and last several months, high temporal resolution information, are necessary. In this manuscript I shall describe how I tried to develop, and to apply, environmental proxies from biocarbonate archives in the tropical Pacific Ocean to reconstruct the monthly or infra-monthly variability of the sea surface temperatures (SSTs) and the evaporation/precipitation balance. To do that, I focused my works on the mollusk shells and Porites sp coral skeleton. These archives contain various tracers (growth and geochemical variations) of the sought environmental variables. I will show that the thicknesses of growth decreases of the Protothaca thaca bivalve shells (East Pacific) indicate occurrences of El Nino events. In the Western part of the Pacific basin, changes in daily increment thicknesses in two Tridacnidae species, Tridacna maxima and Hippopus hippopus are related to SST changes but also depend on physiological condition of the animals. While certain geochemical tracers (Sr/Ca, δ18O) within Porites sp. Skeleton can be used with a certain confidence, this is not always the case for the mollusk shells. I will show that the use of Mg/Ca as a SST proxy depends on the species and that physiology and very early diagenesis are obstacles in the use of this proxy. In T. maxima and H hippopus, δ18O can be used as a tracer of SST and of the evaporation/precipitation balance. To reconstruct variations of these parameters during the Mid-Holocene, I worked on fossil giant clams and corals, after diagenesis assessment. I will show how various types of diagenesis impact the microstructure, the geochemistry, and the reconstructed environmental parameter. I will also propose hypotheses on the diagenesis process itself. Based on results obtained from Mid-Holocene archives, I will show that the post-glacial SST rise was reached at around 6.5-6 ka BP in the Southwest Pacific, that the South Pacific Convergence Zone influence was more probably reduced, the Hadley circulation enhanced, and that ENSO variability was probably reduced. The work done on Lapita (3 ka BP) Tridacnidae confirmed that the Lapita migration has probably been favored by an increase in climatic variability.The last chapter deals with the future directions I would like to give to my research that include i/ better understand the incorporation of proxies in mollusk and ii/ try to propose solution for sustainable management of tropical ecosystems based on the use of biocarbonate as recorder of the environment and its disturbances.; Dans le contexte actuel du changement climatique et la nécessité de fournir des prédictions du climat futur aussi précises que possible, il est primordial de connaître au mieux notre système climatique. L'Océan Pacifique est un compartiment important de ce système, lieu d'interactions océan-atmosphère fortes et où naît l'Oscillation australe El Niño (ENSO), dont les impacts sont catastrophiques pour l'environnement et les populations. Nos connaissances de ce phénomène sont basées en partie sur des observations, qui restent cependant limitées dans le temps. Pour pallier le manque de données et mieux comprendre la variabilité naturelle du climat, des données supplémentaires sont acquises pour des périodes passées à partir de différentes archives. Comme les occurrences ENSO sont liées à la variabilité saisonnière et durent quelques mois, il est nécessaire d'obtenir des données de l'environnement à haute résolution temporelle. Dans ce manuscrit je montrerai comment j'ai tenté de développer, puis d'appliquer, différents traceurs présents au sein d'archives biocarbonatés (mollusques et coraux) pour obtenir des données de la température de surface de l'eau (SST) et de la balance précipitation/évaporation à une échelle mensuelle à infra-mensuelle. Je montrerai que les diminutions de croissance des coquilles du bivalve Protothaca thaca (Pacifique Est) indiquent des occurrences d'événements El Niño. Dans l'ouest du Pacifique, les variations d'épaisseur des incréments journaliers des coquilles de Tridacna maxima et Hippopus hippopus (Tridacnidae) sont liées aux changements de SST mais dépendent également de l'état physiologique des animaux. Alors que certains traceurs géochimiques (Sr/Ca, δ18O) au sein du squelette de Porites sp. peuvent être utilisés avec une certain confiance, ce n'est pas toujours le cas pour les coquilles de mollusques. Je montrerai que l'utilisation du rapport Mg/Ca comme traceur de la SST dépend de l'espèce considérée et que la physiologie et la diagenèse très précoce sont un obstacle à l'utilisation de ce proxy. Au sein de T. maxima and H hippopus, le δ18O peut être utilisé comme traceur des variations de SST et de la balance précipitation/évaporation. Pour reconstruire les variations passées de ces paramètres, des archives fossiles sont utilisées. Je montrerai comment différents types de diagenèse impactent la microstructure, la géochimie, et les paramètres environnementaux reconstruits. Je proposerai également des hypothèses concernant les processus diagénétiques eux-mêmes. A partir d'archives datant de l'Holocène moyen, je montrerai que la remontée des SSTs, après la dernière époque glaciaire, était terminée à partir de 6.5-6 ka BP dans le Sud-ouest Pacifique, que l'influence de la zone de convergence du Pacifique Sud était très probablement réduite, la circulation de Hadley plus importante, et la variabilité ENSO réduite. Les travaux faits à partir de Tridacnidae de sites Lapita (3 ka BP) confirment que la migration Lapita a été favorisée par une augmentation de la variabilité climatique.Le dernier chapitre est consacré aux futures directions que j'aimerai donner à mes travaux de recherches qui incluent entre autres de i/ mieux comprendre les processus d'incorporation des proxies au sein des coquilles de mollusques et ii/ tenter de proposer des solutions pour une gestion durable des écosystèmes tropicaux en utilisant les archives biocarbonatés comme enregistreurs de l'environnement et de ses perturbations.

Coral bleaching events are predicted to occur more frequently in the coming decades with global warming. The susceptibility of corals to bleaching during thermal stress episodes depends on many factors, including the magnitude of thermal stress and irradiance. The interactions among these two factors, and in particular with ultra-violet radiation (UVR), the most harmful component of light, are more complex than assumed, and are not yet well understood. This paper explores the individual and combined effects of temperature and UVR on the metabolism of Acropora muricata, one of the most abundant coral species worldwide. Particulate and dissolved organic matter (POM/DOM) fluxes and organic matter (OM) degradation by the mucus-associated bacteria were also monitored in all conditions. The results show that UVR exposure exacerbated the temperature-induced bleaching, but did not affect OM fluxes, which were only altered by seawater warming. Temperature increase induced a shift from POM release and DOM uptake in healthy corals to POM uptake and DOM release in stressed ones. POM uptake was linked to a significant grazing of pico- and nanoplankton particles during the incubation, to fulfil the energetic requirements of A. muricata in the absence of autotrophy. Finally, OM degradation by mucus-associated bacterial activity was unaffected by UVR exposure, but significantly increased under high temperature. Altogether, our results demonstrate that seawater warming and UVR not only affect coral physiology, but also the way corals interact with the surrounding seawater, with potential consequences for coral reef biogeochemical cycles and food webs., Summary: This study explores the individual and combined effects of temperature and UVR on the metabolism of Acropora muricata, and on the organic matter release and degradation by the associated bacteria.

The Corail™ stem, which was first introduced in 1986, has since been modified twice: first to make the neck thinner and then to change the location of the laser markings. The survival and complications of the first-generation straight, titanium, hydroxyapatite-coated stem are known; however, there is little specific information about the latest-generation stem. This led us to conduct a retrospective study to determine the: (1) long-term survival; (2) clinical and radiographic outcomes; (3) complications; and (4) risk factors for revision of the newest Corail™ stem.The newest Corail™ AMT (Articul/EZE™ Mini Taper) standard stem has comparable survival to prior models.This single-center, retrospective study included 133 patients (140 hips), who underwent primary total hip arthroplasty (THA), between January and December 2004, in which a Corail™ Standard stem was implanted using a posterolateral approach. Patients who underwent revision THA, THA due to femoral neck fracture or who received lateralized (offset) stems were excluded. The mean age at the time of THA was 69±13 years [35-92] in 85 men (61%) and 55 women (39%) who had a mean BMI of 27kg/mThe PMA score was 12±2.6 [5-17] preoperatively and 16±2.7 [7-18] at the last follow-up (P0.00001). Eighteen complications (12.8%) were recorded at the last follow-up. There were 15 early complications: 6 dislocations, 5 calcar fractures (4 treated by wire cerclage and 1 by stem change plus wire cerclage), 2 greater trochanter fractures (treated non-surgically) and 2 cases of sciatic nerve palsy. There were 3 late complications: 2 cases of iliopsoas irritation and 1 ceramic insert fracture. Stem survival for surgical revision due to aseptic loosening was 98% (95% CI: [0.96-1]). At 12 years, 95% of stems had not been revised or removed (95% CI: [0.92-0.99]). Being less than 58 years of age at the time of surgery was the only risk factor significantly associated with stem revision for any reason (P=0.04).Survival of the Corail™ Standard stem is similar to that of previous generation stems. The changes made in this stem solved the neck failure problem and did not induce new complications.Level IV (retrospective study).

INTRODUCTION: Numerous national joint registries demonstrate a trend towards the use of uncemented femoral components in total hip arthroplasty. While the results of first-generation uncemented, and some of the second-generation uncemented implants have been unacceptably poor, others, including the fully hydroxyapatite (HA) coated femoral stems, have been excellent with survival rates of greater than 95% at 20 years. Component longevity is largely related to robust stem fixation to native bone. Adequate stem fixation to the native bone can be determined by clinical assessment and radiological signs of osteointegration. The absence of these radiological signs might be an indication of early loosening. With this in mind, we performed a radiological analysis of the osteointegration of uncemented fully HA-coated femoral stems inserted at our arthroplasty unit. MATERIALS AND METHODS: We performed a retrospective chart and radiological review of patients who had undergone total hip replacement with an uncemented fully HA-coated femoral component over a five-year period. Between March 2003 and March 2008, 80 patients met the criteria used, and radiological changes around the femoral stem were analysed. The mean patient age at the time of surgery was 59 years, and the most common presenting pathology was avascular necrosis (43%). The immediate post-operative, six-week, six-month, one-year and five-year radiographs were evaluated. RESULTS: There were no revisions for stem-related complications. The earliest radiological signs of osteointegration, which included remodelling and trabecular bone formation, were noticed as early as six weeks post-operatively in 4%. At six months and one year, these had increased to 63% and 100% respectively. Thereafter, the radiographs demonstrated minimal change and maintained so-called 'radiological silence'. CONCLUSION: Osteointegration of fully HA-coated stems occurs in a predictable manner, and is noted in radiographs as early as the six-week follow-up period. Signs of osteointegration can be used as reliable indicators of solid femoral stem fixation after total hip replacement