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In February 2021, an explosion of cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia overwhelmed the only hospital in Mayotte. To report a case series of patients with acute respiratory failure (ARF) due to SARS-CoV-2 who were evacuated by air from Mayotte to Reunion Island.This retrospective observational study evaluated all consecutive patients with ARF due to SARS-CoV-2 who were evacuated by air from Mayotte Hospital to the intensive care unit (ICU) of Félix Guyon University Hospital in Reunion Island between February 2, and March 5, 2021.A total of 43 patients with SARS-CoV-2 pneumonia were evacuated by air, for a total flight time of 2 hours and a total travel time of 6 hours. Of these, 38 patients (88.4%) with a median age of 55 (46-65) years presented with ARF and were hospitalized in our ICU. Fifteen patients were screened for the SARS-CoV-2 501Y.V2 variant, all of whom tested positive. Thirteen patients (34.2%) developed an episode of severe hypoxemia during air transport, and the median paO2/FiO2 ratio was lower on ICU admission (140 [102-192] mmHg) than on departure (165 [150-200], P = .022). Factors associated with severe hypoxemia during air transport was lack of treatment with curare (P = .012) and lack of invasive mechanical ventilation (P = .003). Nine patients (23.7%) received veno-venous extracorporeal membrane oxygenation support in our ICU. Seven deaths (18.4%) occurred in hospital.Emergency air evacuation of patients with ARF due to SARS-CoV-2 was associated with severe hypoxemia but remained feasible. In cases of ARF due to SARS-CoV-2 requiring emergency air evacuation, sedated patients receiving invasive mechanical ventilation and curare should be prioritized over nonintubated patients. It is noteworthy that patients with SARS-CoV-2 pneumonia related to the 501Y.V2 variant were very severe despite their young age.

Background: In Reunion Island, influenza is not considered a serious illness despite significant mortality in intensive care unit (ICU). We assess the post-pandemic mortality of influenza by comparing it to other community-acquired pneumonia in our ICU. Methods: Retrospective, descriptive, and single-centre cohort study. The main aim was to determine the standardized mortality ratio (SMR) for influenza based on the quartiles of the SAPSII score in the reference population of 954 patients hospitalized for community-acquired pneumonia. Another aim was to analyze the risk factors for mortality in influenza patients. Results: 127 consecutive patients were hospitalized in our ICU with a positive influenza PCR, from January 2013 to December 2017. The mortality rate of these patients was 31% (CI 95%: 23-39%). In patients hospitalized for community-acquired pneumonia, the SMR of patients with influenza was 1.24 (CI 95%: 0.89-1.70). At admission, thirty-nine patients (31%) had superinfections, in 17 caused by methicillin-susceptible Staphylococcus aureus. Need for renal replacement therapy (RR 2.53 [1.29-4.93]) or ECMO (RR 2.35 [1.16-4.74]) were associated with mortality. Twenty-four patients underwent ECMO, 17 with VV-ECMO. Conclusions: Mortality in patients with influenza pneumonia was higher than the expected mortality in community-acquired pneumonia. Although generally considered benign, influenza is a deadly infection in ICU patients in Reunion Island.

SARS-CoV-2 is an emerging virus responsible for COVID-19 disease which manifests as flu-like and respiratory symptoms but can also have severe neurologic manifestations. We present a case of necrotizing encephalitis.

Objectives: The aim of the present study was to assess the post-pandemic mortality of influenza in patients receiving venovenous extracorporeal membrane oxygenation (VV-ECMO) in Reunion Island, France, by comparing the incidence with other patients undergoing VV-ECMO. Design: Retrospective, descriptive, and single-center cohort study. The primary outcome was the standardized mortality ratio for influenza based on the quartiles of the Respiratory Extracorporeal Membrane Oxygenation Survival Prediction score (RESP Score) in the reference population of patients undergoing VV-ECMO. Setting: Intensive care unit (ICU), Felix Guyon Hospital, University Teaching Hospital of La Reunion, La Reunion, France. Participants: Consecutive patients on ECMO with positive polymerase chain reaction for influenza. Interventions: None. Measurements and main results: One hundred twenty-seven consecutive patients were hospitalized in the ICU with a positive influenza polymerase chain reaction from January 2013 to December 2017. Twenty-four influenza patients underwent ECMO including 18 patients with VV-ECMO. During this period, 72 patients requiring VV-ECMO were hospitalized in the ICU. The overall mortality rate of influenza patients on VV-ECMO was 61% versus 46% for non-influenza patients. The standardized mortality ratio per quartile of RESP Score was 1.28 (95% confidence interval 0.61-2.35). Conclusions: In Reunion, the mortality of patients undergoing VV-ECMO for severe influenza is not lower than the expected mortality of all patients undergoing VV-ECMO.

chemical and physical disruption of the aquatic ecosystems. Regulations, such as the EU Water Framework Directive, for the protection of the aquatic environment, encourage the development of new sensitive and predictive tools to evaluate the effects of contaminants on aquatic living organisms. In this context, energy metabolism biomarkers are of interest given the central place of energy in all physiological processes (i.e. defense, growth and reproduction). In this study, we addressed for the first time three digestive enzymes (amylase, trypsin and intestinal alkaline phosphatase) and evaluated their interest as novel biomarkers in the threespine stickleback (Gasterosteus aculeatus), a model species in multidisciplinary fields of biology, and recently in ecotoxicology. The interest of the two digestive enzymes as biomarkers was evaluated in comparison with other parameters, usually applied in ecotoxicology studies: biometric parameters, reproduction parameters, antioxidant parameters, and other energy metabolism parameters. For that, juvenile sticklebacks were exposed for 3 months in semi-static conditions to cadmium at 0.5 μg.L-1 (chemical stress), and two water temperatures 16°C and 21°C (physical stress). Results showed that the high temperature (21 °C) was the major stress factor on stickleback physiology. The very low cadmium concentration used in this study had no effect on most of the studied parameters (i.e. growth parameters, antioxidant parameters and parents' reproduction parameters). However, digestive enzymes showed an interesting sensitivity to cadmium exposure which was emphasis at 21 °C (significant decrease). Although cadmium had no effect on parental reproduction, negative consequences on their offspring survival were observed after in vitro fertilization trials (decreased survival capacity). Compared to conventional measurements, digestive enzymes responded rapidly, which could be an important advantage for their use as early warning tool, to reflect organism’s health.

The zebra mussel is among the best studied freshwater molluscs in ecotoxicology, but information on the quagga mussel is lacking. Considering its potential spread, we selected a river in France in which zebra and quagga mussels coexisted, and then we used genetic markers to differentiate the two species and compared morphological parameters. cDNA sequencing assays of ten genes already used in zebra mussels were performed on quagga mussels to obtain functional specific primers. Then we analyzed the expression of genes involved in cellular metabolic activities (Cytochrome-c-oxidase - cox, and ATP synthase - atp), detoxification processes (Glutathione-S-Transferase - gst), oxidative stress (Catalase - cat), and digestive functions (Amylase - amy) on the two species. Whereas morphometric analysis underlined similarities in shape between the two species, relative gene expression profiles and metal concentrations evidenced strong differences. Quagga mussels notably presented half as high concentrations in Cd and Pb, two particularly toxic elements, as zebra mussels. These results imply that i) particular attention should be paid to properly distinguish the two species considering their similar external appearance, and ii) zebra mussels cannot be replaced by quagga mussels in ecotoxicological studies without preliminary investigations on biomarker response patterns. To our knowledge, this study is the first to have undertaken such an approach in gene expression analysis in quagga mussels, and more generally to have compared such biomarker responses of zebra and quagga mussels in the field.

International audience; Determining digestive enzyme activity is of potential interest to obtain and understand valuable information about fish digestive physiology, since digestion is an elementary process of fish metabolism. We described for the first time (i) three digestive enzymes: amylase, trypsin and intestinal alkaline phosphatase (IAP), and (ii) three gut morphometric parameters: relative gut length (RGL), relative gut mass (RGM) and Zihler's index (ZI) in threespine stickleback (Gasterosteus aculeatus), and we studied the effect of temperature and body size on these parameters. When mimicking seasonal variation in temperature, body size had no effect on digestive enzyme activity. The highest levels of amylase and trypsin activity were observed at 18°C, while the highest IAP activity was recorded at 20°C. When sticklebacks were exposed to three constant temperatures (16, 18 and 21°C), a temporal effect correlated to fish growth was observed with inverse evolution patterns between amylase activity and the activities of trypsin and IAP. Temperature (in both experiments) had no effect on morphometric parameters. However, a temporal variation was recorded for both RGM (in the second experiment) and ZI (in both experiments), and the later was correlated to fish body mass.

Coastal flooding is a temporary flood of a coastal area by the sea due to extreme weather conditions causing sea level rise. These conditions are generally caused by atmospheric depression, severe wind and high swell with specific detrimental tidal conditions. After the storm Xynthia and its tragic consequences on the French Western seaside (Vendee area) in February 2010, measures have been implemented by the French authorities in order to manage these events. One of these measures is to implement Coastal Risk Management Plans. These plans aim to delimit areas exposed to the risk of marine flooding and erosion and to define regulations about land use depending on the intensity of hazards and issues. In collaboration with the Ille-et-Vilaine Departmental Directorate of Territories and the Sea, DHI has been commissioned to take part in generating such a plan for the city of Saint-Malo (Brittany) and to implement a hydrodynamic model. Thus a coupled 1/2D model is set up with MIKE FLOOD and different scenarios of failure of sea defence structures are tested. Different types of failures are considered like breaches in the dikes, overflows when the sea level is higher than the structure level and wave overtopping due to wave run-up. Failure locations are defined according to topographical analyses, study of structure shapes, knowledge about historical events and feedback about accidentology and analyses of marine energy. In order to take into account the effect of climate change, current sea level and projected sea level for the year 2100 are considered. These levels are based on reference levels, wave set-up and uncertainty margin. The model is defined with a regular mesh with a 3-m-grid resolution. LIDAR surveys are used to represent the topography of the area. In order to be more accurate, wastewater networks are modelled with MIKE URBAN too and their effect to alleviate the flood propagation is highlighted. The dysfunction of a pumping station is considered too. After the modelling tasks, hazard maps are generated. These maps represent the intensity of the events based on the simulation outputs linked to water depth and flow velocity. Then, mapping flooded issues leads to divide the area in four main types of land use: urban spaces, natural spaces, historical urban centre and port area. Finally, a coastal risk regulatory zoning is generated by crossing hazard maps and issues maps. The area is then divided into different classes and each class is defined by a specific regulation about land use and building authorisation procedures depending on the hazardousness and the type of issues.

Oil spill experience often shows that response activities are hampered due to the absence of operative autonomous support capable of reaching particular sites or operate in safe and efficient conditions in areas such as saltmarshes, mudflats, river banks, cliff bottoms… This is the purpose of the so-called FP7 Hoverspill project (www.hoverspill.eu), a 3-year European project that recently reached completion: to design and build a small-size amphibious vehicle designed to ensure rapid oil spill response. The result is an air-cushion vehicle (ACV), known as Hoverspill, based on the innovative MACP (Multipurpose Air Cushion Platform) developed by Hovertech and SOA. It is a completely amphibious vehicle capable of working on land and on water, usable as a pontoon in floating conditions. Its compactness makes it easy to transport by road. The project also included the design and building of a highly effective integrated O/W Turbylec separator developed by YLEC. Spill response equipment will be loaded on-board based on a modular concept enabling the vehicle to carry out specific tasks with just the required equipment.

International audience; The present study was performed to validate the suitability of using gene expression in zebra mussels, Dreissena polymorpha, for biomonitoring of freshwater environment. Mussels were collected in four French rivers (Meuse, Moselle, Oise and Vilaine) in spring and autumn. Relative gene expression of 9 candidate genes involved in cellular metabolic activities (Cytochrome-c-oxidase - cox, and ATP synthase - atp), detoxification process (Metallothionein - mt and Glutathion-S-Transferase - gst), oxidative stress (Catalase - cat, Superoxyde Dismutase - sod and Glutathion peroxidase - gpx) and digestive functions (Amylase - amy and Cellulase - ghf) were measured in digestive gland. Metal bioaccumulation in tissues and morphometric parameters were also analyzed to interpret molecular responses. All our results are consistent with different physiological reactions to environmental condition between zebra mussel populations. In spring, the levels of mt, sod, gpx, cat, atp, amy and ghf relative expression were significantly higher in mussels with the lowest metal bioaccumulation (the Meuse) compared to at least one of the other sites. In autumn, this higher expression levels in Meuse River were still observed for gpx, cat, atp and amy. This study has also pointed out different sources of variability in gene expression (individual size, season, trophic resources and origin of mussels) which are inevitable in natural fluctuant environment. This underlines the importance to take them into account in field study to propose a correct interpretation of biomarker responses.

The three-spined stickleback, is a freshwater, brackish, and marine fish species with large distribution throughout the northern Hemisphere. This pollution-tolerant fish is present in most European streams and small rivers but also coastal and estuarian areas, which make it a suitable candidate for environmental monitoring and risk assessment of aquatic ecosystems. Several biomarkers have been developed for this animal model. This study aims at characterizing and developing a new category of biomarkers in relation with energy acquisition, in sticklebacks. Among these parameters, digestive capacities of many invertebrates and vertebrates aquatic organisms have demonstrated a good sensitivity to contaminants. Thus, in this context, the most important digestive enzymes were firstly characterized in this sentinel species, according to it diet, in optimal living conditions. Secondly male and female juvenile sticklebacks were exposed for 3 months in semi-static conditions to cadmium at 1µg.L-1 (chemical stress), and two temperature values 16°C and 21°C (physical stress). Water quality and cadmium concentration in the water were also monitored throughout the experiment. Parameters such as somatic indexes (height, weight, fulton’s condition index) and digestive enzymes (trypsin, intestinal alkaline phosphatase and amylase) were measured at 15, 60 and 90 days interval after cadmium exposure. The results have demonstrated a significant decrease in biometric parameters, from the 3rd month, especially among groups subjected to a temperature of 21 ° C. Furthermore, we observed an important alteration of the activity of the different enzymes over time and especially for trypsin and alkaline phosphatase in individuals exposed to cadmium at 21°C suggesting interactions between chemical and physical stresses on biological responses. For the first time, the digestive enzymes of the three-spined stickleback are reported as new environmental biomarkers.

International audience

Aims The objective of this study was to evaluate if freshwater bivalves can be used to detect the presence of Toxoplasma gondii in water bodies. Methods and results Zebra mussels (Dreissena polymorpha) were caged for 1 month upstream and downstream of the discharge points of wastewater treatment plants (WWTPs). Physiological status was assessed to assure good health of bivalves during transplantation. The presence of T. gondii was investigated in mussel tissues by qPCR. In autumn, T. gondii was detected in mussels caged downstream of the discharge points of two WWTPs. In spring, it was detected upstream of one WWTP. Conclusions For the first time, T. gondii DNA has been shown in a continental mollusc in environmental conditions. This highlights the interest of an active approach that could be applied independently of the presence or accessibility of autochthonous populations, and underlines the presence of T. gondii in natural waters under pressure of WWTP discharge at a certain time of the year. Significance and impact of the study This study shows that transplanted zebra mussels could be used as biosamplers to reveal contamination of freshwater systems by T. gondii.

Field caging experiments were conducted on 0-group juvenile sea bass ( Dicentrarchus labrax ) and turbot ( Scophtalmus maximus ) in a polluted area. The fish were caged for 38 days in a northern French harbour (Boulogne sur Mer) at three locations with varying levels of contamination. Sediment from each location was analysed for PAHs, PCBs and metal contents, and their respective bioavailability. In the most heavily contaminated station, all the fish died during the two first weeks. At the two other stations, fish recovery was at least 75%. Growth and several health indices were individually measured on the tagged fish and metal bioaccumulation was measured in the fish gills. Juvenile sea bass physiological performance showed significantly higher growth rates, RNA:DNA ratio and Fulton's K condition index in the least contaminated station. The growth in weight and the condition index of the turbot caged in the less contaminated station were also higher. Similarly, for both species, lipid storage index based on the ratio of the quantity of triacylglycerols to sterols (TAG:ST), was significantly higher in the less contaminated station. This general decrease of growth and condition indices, associated with a metal accumulation in gills, reflected the adverse effects of contaminated sediment on the health of the fish. Species-specific responses to chemical contamination were recorded since a stronger relationship between physiological biomarkers and chemical contamination was observed in the sea bass. Therefore, this study supports the use of sea bass as model species and recommends measurements of physiological biomarkers for monitoring complex exposure.

Since sediments have the potential to form associations with several classes of pollutants, they have been recognized as a possible and significant source of contamination for the benthic environment. Flatfish maintain a close association with sediments for food and cover, and are therefore more likely to be exposed to contaminated sediments, especially in coastal areas (e.g. nursery grounds). The assessment of these potential biological effects involves the use of adapted biomonitoring tools. The main objective of this study was to assess and compare the response of several physiological biomarkers measured on juvenile turbot (Scophthalmus maximus) exposed to contaminated sediments. Sediments were collected from three stations in a harbour in northern France (Boulogne-sur-Mer), in an anthropogenic French estuary (the Seine), and in a reference site (exposed sandy beach of Wimereux). Unexposed lab-reared juvenile turbots were exposed to sediments for 7 and 21 days in laboratory conditions. Sediments were analysed for metals, PAH and PCB contamination. Several fish growth and condition indices were individually analysed in fish according to the chemical contaminant availability in sediment, the metal concentrations in gills and the estimation of PAH metabolites in their bile. Significant decreases in growth rates, morphometric index, RNA:DNA ratio and the lipid storage index, based on the ratio of the quantity of triacylglycerols on sterols (TAG:ST), were observed with increasing level of chemical contamination. This decrease in the fish's physiological status could be related to the significant increase of several metal concentrations in contaminated fish gills and the significant increase of PAH metabolites in bile. In a field situation, such a reduction in growth and energetic status of juvenile fish could dramatically decrease their over-winter survival in contaminated nursery grounds.

International audience

To characterize environmental risks linked to former uranium mines in the Limousin region of France, a study was conducted on fish health effects from uranium releases. Two private ponds were compared in this study, one with uranium contamination and one background site, upstream of the mining zone. Roach, Rutilus rutilus, were caged for 28 days in both ponds. Physico-chemical parameters of water and sediments and bioaccumulation of metals in several organs were determined. After 14 and 28 days of caging, immune, oxidative stress, biotransformation, neurotoxicity and physiological parameters were measured. Iron and aluminium were quantified in the water of both sites; however, barium and manganese were only present in the water of the uranium contaminated site. Uranium was present in both sites but at very different concentrations. The sediments from the uranium contaminated site contained high levels of radioactive elements coming from the disintegration chain of uranium. Results of biological parameters indicated stimulation of immune parameters and of oxidative stress and a decrease of AChE in fish caged in the uranium contaminated pond compared to the uranium-free pond. Overall, the results determined roach health status in the context of pollution from poly-metallic mining. The data strengthen our knowledge of the environmental risk assessment associated with radioactive substances in the environment.

Endless stretches of cliffs with deep coves and caves were coated with Heavy Fuel Oil during the Erika oil spill. Professional rope workers were called in to help clean the cliffs and the coves as most of them were located in protected reserves. This was the very first time that such a technique was used to clean up pollution and it turned out to be original if only because of the size of the job to be done. The clean-up operation lasted two and a half years, involved over 800 work sites and the rope workers cleaned up more than 50 of them. As a rule, cliffs that are hard to access are not cleaned up if only for safety and logistics reasons. There were various reasons why so many work sites had to be set up during the Erika clean-up, namely: the nature and the quantities of the HFO, the ecological, amenity and heritage importance of the area, the know how and the complementarity of the rope workers and the clean-up companies that continually improved their techniques and their efficiency as time went by. Thanks to compliance with rules and safety standards there were no accidents.

The zebra mussel Dreissena polymorpha is a fresh water bivalve considered as suitable monitoring organisms because of it abundance, wide distribution and interesting responsiveness to pollutant. However it also presents a sensibility to variation of environmental parameters, particularly to modification of the nutritive capacity of the environment. So the nutritional state of mussels may constitute a confounding factor in ecotoxicological survey. The non-steroidal anti-inflammatory drug diclofenac is one of the most used drug in France (10 tons per year) and it is part of the three pharmaceuticals proposed for the Water Framework Directive's priority list of pollutant in surface waters. Few data exist on its effect on bivalves. So the goal of this study was to assess the impact of this drug on reproductive apparatus of the zebra mussel. In this aim mesocosm approach was developed with 12 artificial canals and a flux of water containing 0, 0.1, 1 or 10 µg/l of diclofenac in triplicate. The histopathological alterations eventually induced were analyzed in 10 to 20 mussels after 0, 46, 64 and 160 days. However, it appeared that the diclofenac have an impact on macrophyte and periphyton biomass and distribution. To analyze the effect of nutritive stress on gonadic structure of the bivalve, zebra mussels were placed during 150 days in aquarium and fed two time per week by controlled alga volume (Scenedesmus obliquus and chlorella) in duplicate: 100 000 cells (ad libitum diet called 100%), 10 000 cells (10 %) or to 0 alga (0%). Observed ovary histopathological alterations induced by diclofenac (follicle atresie, oocyte necrosis, perifollicular fibrosis, decrease in mature ovocyte production) revealed the gonadic toxicity of this drug. The nutritive stress (10 %) and the total food deprivation (0%) also produced important alterations of the mussel ovary development (follicle atresie, reduction of mature oocyte size). However in the mesocosm experiment the mussel diet was modified but not severally reduced. Moreover the gonadic alterations observed with diclophenac were not similar to these obtained with nutritive deprivation. So it was possible to conclude that the gonadic alterations observed depended mostly of diclofenac direct toxic impact. These results were discussed with amounts of energetic reserves, activity of digestive enzymes and foot protein expression in order to better appreciate the way that Dreissena polymorpha adapt to nutritive deprivation.

In coastal environments, salinity variations may affect phases in crustacean reproductive cycle. Brown shrimp Crangon crangon Linnaeus, 1758 (Decapoda) are known to undertake breeding migrations between the sea and coastal waters (lagoons, estuaries). After a major flooding, the salinity of the Vaccares coastal lagoon (Rhone River delta, France) dropped from 15‰ to 5‰ in a few days and remained low during following years. The aim of this study was to assess the impact on this environmental change on the reproduction of brown shrimp. We first tested whether females C. crangon had the ability to become ovigerous at a salinity as low as 5‰. Furthermore, the question whether salinity had an impact on fecundity was addressed. Experiments in aquaria were carried out for 180 days in the laboratory, with three replicates at three salinities (5, 15, and 25‰ respectively), keeping local photoperiod and temperature. Mortality was significantly higher in tanks at 5‰ than in those at higher salinities. Female...

Environmental factors, especially salinity, play a major role in the life cycle and ecology of aquatic organisms. Hundred year return-time floods in the river Rhone (southern France) in the winter ...

Since 1966, huge inputs from the Durance river diverted into the ‘etang de Berre’ (Mediterranean sea, France) have modified the hydrology, hydrodynamics and sedimentation patterns. Aerial photography allowed us to depict the surface dispersal of silt-loaded waters, and to locate turbulent phenomena. Hypersedimentation areas, evidenced through comparison of 1962 and 1992 bathymetric surveys, coincide with front and water mixing zones identified since 1970 from aerial observations.

We examined the hypothesis that metazoan zooplankton may directly influence on microbial populations in an oligotrophic marine system. Diel variations of microbial populations, relative to changes in the biomass and feeding activity of metazoan zooplankton, were studied at an offshore station in the North Western Mediterranean Sea. Two different parts of the water column, representing relatively low, 0.05 μg l −1 , and high, 0.12 μg l −1 , chlorophyll zones were repeatedly sampled. At 3 h intervals, samples were obtained from 5 m and 40 m for estimates of microbial population abundances, size-fractions of chlorophyll and bacterial production; metazoan zooplankton were sampled concurrently with vertical net hauls between 0 and 50 m. Overall, there were no large day/night differences or clear diel rhythms in parameters of microbial populations. Bacterial concentrations peaked in the early evening at 40 m and later at 03:00 h at 5 m depth. Cell specific thymidine incorporation rates showed a distinct peak in the early morning hours at 5 m and were nearly constant at 40 m. Photosynthetic and heterotrophic nanoflagellates showed dissimilar temporal trends both relative to one another and between the two sampling depths. Chlorophyll, in the 10 μm was a negligible part of the chlorophyll crop at 5 m but represented about 50% of the chlorophyll at 40 m and showed considerable variability. In contrast to parameters of microbial populations, we found clear and large day/night differences in both abundances and feeding activities of metazoan zooplankton. Abundances of total zooplankton were higher by about a factor of 4 during nightime hours. Metazoan zooplankton peak abundances occurred from midnight to 03:00 h corresponding with peak activities of the digestive enzymes amylase and trypsin in total zooplankton as well as gut fluorescence in the most abundant copepod, Centropages typicus . There were few significant relationships detectable between parameters of microbial populations and metazoan zooplankton. The link between metazoan zooplankton and microbial populations, even in low-chlorophyll surface waters was apparently weak.

Two aspects of the physiology of the burrowing shrimp Caliianassa tyrrhena (Decapoda: Thalassinidea) were studied in order to investigate the effects of the general pollution load: total (TRR) and weight-specific respiration rate (SRR) as well as the digestive enzyme activity of the digestive gland.Caliianassa tyrrhena exhibited a very low respiration rate (mean TRR=64-29 μl 02 animal−1h−1, N=60; mean SRR=0·18 μl 02mg DW−1h−1, N=61).The slope of the TRR-DW logarithmic regression (b=0·64) showed that respiration in C. tyrrhena is proportional to body surface. Size is the dominant factor (among size, sex, season and locality) determining the variation in respiration rate. Comparison between the two sites with the different pollution load showed that there were no significant differences in the respiration rates of the same size class and season, except for the youngest animals in summer which showed a significant decrease in their respiration rate at the polluted site.A similar ‘inhibitory’ effect of pollution has been observed in the activity of the majority of the 19 digestive enzymes tested. Only three e.g., trypsin, β-galactosidase and α-glucosidase showed an increase in polluted waters.One could suggest, therefore, that C. tyrrhena can be considered to be preadapted to the low oxygen conditions encountered in the sediments, because of its burrowing mode of living.

A 4 pi charged particle detector array with a low velocity threshold has been used to detect the products from reactions induced by Ar-36 on Al-27 at energies ranging from 55 to 95 MeV/u. Well characterized events were selected and sorted as a function of the impact parameter. Two methods were used for sorting these events with respect to their impact parameters and three methods were compared to determine the reaction plane. The transverse momentum analysis has been found to be the best method to extract the direction of the reaction plane for this system and for the experimental set-up used here. The energy of vanishing flow for central collisions has been found to be around 90-95 MeV/u. The azimuthal distributions of mid-rapidity particles exhibit a preferential in-plane emission and no squeeze-out effect.

The objective of the present study is to examine the growth and energetic performance of juvenile turbot after exposure to contaminated sediment and during the subsequent recovery period with or without food limitation. We designed a two-step experiment by first exposing juvenile turbot to harbour sediment for 26 days and then transferring them to clean sea water with different frequencies of feeding for 35 days. Without food limitation, fish previously exposed to contaminated sediment compensated for weight, length and lipid reserve losses; we did not record any differences in size, Fulton’s K condition index and triacylglycerol/sterol (TAG/ST) ratio after the 35-day depuration period compared to the reference fish. This result could be related to the compensatory growth mechanism observed in a wide range of fish species following a period of growth depression. With food limitation during the 35-day depuration period, recovery growth was not sufficient to restore length and weight values similar to the reference fish. Moreover, turbot previously exposed to contaminated sediment and subsequently fed twice or once a week exhibited extremely low TAG/ST ratios, but the reference fish submitted to the same restrictive feeding conditions did not. This study indicates that juvenile fish affected by chemical pollution can improve their biological performance if pollution events are followed by a period of abundant food. However, if pollution events occur during periods of food scarcity, e.g. in winter, storage of energy reserves will be compromised.