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International audience; The design and the grazing flow aeroacoustical characterization of a 2D active liner based on an array of electroacoustic absorbers are presented in this paper. The strategy stands on a pressure-based, current-driven digital architecture for impedance control with both local and non local architectures. A wind tunnel test rig is used for the in-flow experimental validation. The stability and robustness of the whole system are investigated as a function of flow velocity showing the efficiency of the proposed approached. The air flow slightly reduces the efficiency while maintaining the adaptability and the stability, and better performances are obtained with the non local control strategy.

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Background: Mercury is known to bioaccumulate and to magnify in marine mammals, which is a cause of great concern in terms of their general health. In particular, the immune system is known to be susceptible to long-term mercury exposure. The aims of the present study were (1) to determine the mercury level in the blood of free-ranging harbour seals from the North Sea and (2) to examine the link between methylmercury in vitro exposure and immune functions using seal and human mitogen-stimulated peripheral blood mononuclear cells (T-lymphocytes). Methods: Total mercury was analysed in the blood of 22 harbour seals. Peripheral blood mononuclear cells were isolated from seals (n=11) and from humans (n=9). Stimulated lymphocytes of both species were exposed to functional tests (proliferation, metabolic activity, radioactive precursor incorporation) under increasing doses of methylmercury (0.1 to 10 mu M). The expression of cytokines (IL-2, IL-4 and TGF-beta) was investigated in seal lymphocytes by RT-PCR and by real time quantitative PCR (n=5) at methylmercury concentrations of 0.2 and 1 mu M. Finally, proteomics analysis was attempted on human lymphocytes (cytoplasmic fraction) in order to identify biochemical pathways of toxicity at concentration of 1 mu M (n=3). Results: The results showed that the number of seal lymphocytes, viability, metabolic activity, DNA and RNA synthesis were reduced in vitro, suggesting deleterious effects of methylmercury concentrations naturally encountered in free-ranging seals. Similar results were found for human lymphocytes. Functional tests showed that a 1 mu M concentration was the critical concentration above which lymphocyte activity, proliferation and survival were compromised. The expression of IL-2 and TGF-beta mRNA was weaker in exposed seal lymphocytes compared to control cells (0.2 and 1 mu M). Proteomics showed some variation in the protein expression profile (e. g. vimentin). Conclusion: Our results suggest that seal and human PBMCs react in a comparable way to MeHg in vitro exposure with, however, larger inter-individual variations. MeHg could be an additional cofactor in the immunosuppressive pollutant cocktail generally described in the blood of seals and this therefore raises the possibility of additional additive effects in the marine mammal immune system.

Objectives: To reconsider the aims of screening for\ud undiagnosed diabetes, and whether screening should be\ud for other abnormalities of glucose metabolism such as\ud impaired glucose tolerance (IGT), or the ‘metabolic\ud syndrome’. Also to update the previous review for the\ud National Screening Committee (NSC) on screening for\ud diabetes, including reviewing choice of screening test;\ud to consider what measures would be taken if IGT and\ud impaired fasting glucose (IFG) were identified by\ud screening, and in particular to examine evidence on\ud treatment to prevent progression to diabetes in these\ud groups; to examine the cost-effectiveness of screening;\ud and to consider groups at higher risk at which\ud screening might be targeted.\ud \ud Data sources: Electronic databases were searched up\ud to the end of June 2005.\ud \ud Review methods: Literature searches and review\ud concentrated on evidence published since the last\ud review of screening, both reviews and primary studies.\ud The review of economic studies included only those\ud models that covered screening. The new modelling\ud extended an existing diabetes treatment model by\ud developing a screening module. The NSC has a set of\ud criteria, which it applies to new screening proposals.\ud These criteria cover the condition, the screening test\ud or tests, treatment and the screening programme.\ud Screening for diabetes was considered using these\ud criteria.\ud \ud Results: Detection of lesser degrees of glucose\ud intolerance such as IGT is worthwhile, partly because\ud the risk of cardiovascular disease (CVD) can be\ud reduced by treatment aimed at reducing cholesterol\ud level and blood pressure, and partly because some\ud diabetes can be prevented. Several trials have shown\ud that both lifestyle measures and pharmacological\ud treatment can reduce the proportion of people with\ud IGT who would otherwise develop diabetes. Screening\ud could be two-stage, starting with the selection of\ud people at higher risk. The second-stage choice of test\ud for blood glucose remains a problem, as in the last\ud review for NSC. The best test is the oral glucose\ud tolerance test (OGTT), but it is the most expensive, is\ud inconvenient and has weak reproducibility. Fasting\ud plasma glucose would miss people with IGT. Glycated\ud haemoglobin does not require fasting, and may be the\ud best compromise. It may be that more people would\ud be tested and diagnosed if the more convenient test\ud was used, rather than the OGTT. Five economic\ud studies assessed the costs and short-term outcomes of\ud using different screening tests. None examined the\ud long-term impact of different proportions of false\ud negatives. All considered the costs that would be\ud incurred and the numbers identified by different tests,\ud or different cut-offs. Results differed depending on\ud different assumptions. They did not give a clear guide\ud as to which test would be the best in any UK screening\ud programme, but all recognised that the choice of cutoff\ud would be a compromise between sensitivity and\ud specificity; there is no perfect test. The modelling\ud exercise concluded that screening for diabetes appears\ud to be cost-effective for the 40–70-year age band, more\ud so for the older age bands, but even in the 40–49-year\ud age group, the incremental cost-effectiveness ratio for\ud screening versus no screening is only £10,216 per\ud quality-adjusted life-year. Screening is more costeffective\ud for people in the hypertensive and obese\ud subgroups and the costs of screening are offset in\ud many groups by lower future treatment costs.

The diagnostics of focal nodular hyperplasia is reached through the use of imaging. When the diagnostic is certain, surgical abstention is the rule. Nevertheless, we were confronted with two cases of a rare complication; that of intraperitoneal rupture. In this situation, we suggest to first do an arteriography to control the bleeding, then to perform surgery when the patient has reached hemodynamic stability. Spontaneous rupture as a complication of benign nodular hyperplasia remains a rare event and only five cases were reported in litterature.

L’appétibilité est le seul critère de consommation des fourrages mesurable sur animaux par les sélectionneurs. On estime la valeur de ce critère en donnant le choix à ces animaux. Un tel test s’appelle une cafétéria. Habituellement, il s’effectue par pâture d’essais. Ces cafétérias de pâture ont divers inconvénients, en particulier ils ne permettent pas de mesurer le rendement et l’appétibilité sur un même essai. Une cafétéria d’auges, qui évite ces inconvénients, est présentée ici. Peu onéreuse et facile à utiliser, elle est fidèle, fiable et très précise, à condition de respecter quelques précautions dont les deux principales sont : tester l’appétibilité dans les quelques heures qui suivent la coupe et opérer sous abri., Palatability is the only intake character measurable on animals by the plant breeder. It is obtained by giving the animals free choice. Such a test is called cafeteria. It is usually carried out by grazing trials. There are some drawbacks to such grazing cafeteria particularly since it is not possible to measure yield and palatability in the same trial. A trough cafeteria that avoids these drawbacks is presented here. Cheap and easy to utilize, it is reliable and very precise, provided a few precautions are observed, the two main ones being : testing palatability within a few hours after the cut, and working under a shelter.

Lorsqu’on double artificiellement le nombre de chromosomes d’une plante, on observe souvent à la génération Co une dépression importante, du même ordre de grandeur que la dépression due à l’inbreeding. Dans les deux cas, on a affaire à un nombre double de chacun des allèles, c’est-à-dire à des situations « consanguines ». Ceci pourrait signifier un effet défavorable des interactions entre gènes identiques elles-mêmes, distinct de l’absence d’interactions favorables entre gènes différents (homéostase, dominance, superdominance, etc...). En effet, le doublement chromosomique ne modifie aucune des balances géniques dans la plante. C’est pourquoi nous pensons que notre hypothèse pourrait faire l’objet de recherches., Doubling chromosome number in a plant frequently results, at the Co generation, in significant depression of the same order of magnitude as inbreeding depression. Both bring about a double number of any given allele, giving rise to « inbred » situations. This could mean a harmful effect of interactions between identical genes per se as distinct from the lack of favourable interactions between different genes (homeostasis, dominance, superdominance), because doubling chromosome number does not alter any genetic balance in the plant. Hence we think that investigation on this hypothesis could be interesting.

Pour pouvoir tester un nombre suffisant de génotypes pour leur aptitude à être bien consommés, les sélectionneurs de graminées sont obligés de donner le choix aux animaux. Nous avons monté une expérience pour étudier, sur 6 génotypes, les corrélations entre, d’une part, l’appétibilité mesurée avec des moutons en cafétéria d’auges, d’autre part, l’ingestibilité et la digestibilité mesurées avec des moutons en cage. L’étude a porté sur 1 brome, 2 ray-grass d’Italie et 3 fétuques élevées. Deux des fétuques ont été également étudiées à l’aide de chèvres laitières. Cette expérimentation a donné des résultats inattendus : - aucune corrélation n’est apparue entre l’ingestibilité et les deux autres critères : digestibilité (mesurée avec les mêmes moutons) et appétibilité. Ceci reste vrai, même lorsque des différences significatives existent entre variétés pour ces trois critères. - l’appétibilité et la digestibilité (mesurées avec des moutons différents) ont généralement été liées entre elles. - le classement de deux fétuques pour la production de lait de chèvres a été le même que leur classement pour l’appétibilité et la digestibilité avec des moutons. - le classement entre espèces obtenu avec la cafétéria a été le même que celui généralement indiqué par les agriculteurs : brome > ray-grass > fétuque élevée. L’ingestibilité, mesurée en cages, a donné un classement différent : ray-grass≥ fétuque = brome. Une question se pose alors : pour déterminer les quantités ingérées par des animaux en conditions agricoles, le problème des préférences ne jouerait-il pas un rôle plus important qu’on ne le croit généralement et, en tout cas, plus important que dans le cas de moutons en cages ?, In order to check a sufficiently large number of genotypes for their consumability, grass breeders cannot avoid giving free choice to the animals. We have carried out an experiment to study, on 6 genotypes, the correlations between palatability as measured with sheep in a trough cafeteria on one hand, and intake and digestibility as measured with sheep in crates on the other hand. The experiment was carried out on one bromus, two rye grasses and three tall fescues. Two of the fescues were also studied with dairy goats. We have obtained the following results : 1) no correlation appeared between intake and the other two criteria : digestibility (measured with the same sheep) and palatability. This was true, even when significant differences between varieties came out for the three criteria. 2) palatability and digestibility (measured with different sheep) were correlated. 3) the ranking of the two fescues for goat milk production was the same as their ranking for palatability and digestibility for sheep. 4) the three species ranked with the cafeteria in the same way as generally indicated by farmers : bromus > rye grass > fescue. Intake in crates ranked differently : rye grass ≥ fescue = bromus. The question thus arises : in determining intake by animals under farm conditions, might the problem of palatability not be more important than usually thought, at least more important that it is for sheep in crates ?