Répartition en Suisse et en France de Sorex araneus L., 1758 et de Sorex coronatus Millet, 1828 (Mammalia, Insectivora)

La répartition en Suisse et en France de Sorex coronatus et de Sorex araneus est étudiée au moyen de l'analyse ostéométrique des mandibules mise au point récemment (Hausser et Jammot, 1974). Nous discutons la mise en pratique de cette méthode. 1 101 exemplaires provenant de 207 localités ont été étudiés. Ces données s'ajoutent aux informations cytologiques obtenues antérieurement pour 65 localités. Les résultats indiquent que S. coronatus et S. araneus ne sont pas sympatriques, sauf éventuellement sur la frange nord-est de l'aire de répartition de la première espèce. Celle-ci semble progresser vers l'est et éliminer peu à peu S. araneus, sauf en montagne, où demeurent des populations isolées et, dans une moindre mesure, dans les lieux humides.

Biosphere/lithosphere interface : microbially-mediated CaCO3 precipitation in hypersaline and freshwater environments

Abstract: Microbial mats very efficiently cycle elements, such as C, 0, N, S and H, which makes them key players of redox processes at the biosphere-lithosphere interface. They are characterized by high metabolic activities and high turnover rates (production and consumption) of biomass, which mainly consists of cell material and of extracellular organic matter (EOM). The EOM forms a matrix, embedding the microbial cells and fulfilling various functions within the microbial mat, including: mat attachment to surfaces; creation of micro-domains within the mat; physical stabilization under hy- drodynamic stress and the protection of the cells in multiple other stress conditions. EOM mainly consists of polysaccharides, amino acids, and a variety of chemical func-tional groups {e.g., -C00H, - SH -OH). These groups strongly bind cations such as Ca2+ and Mg2+ and thus exert a strong control on carbonate mineral formation within the microbial mat. A feedback mechanism between community metabolisms, their prod¬ucts, and the surrounding physicochemical microenvironment thus influences the de¬gree of carbonate saturation favoring either carbonate precipitation or dissolution. We investigated the driving forces and mechanisms of microbialite formation in the Sari ne River, FR, Switzerland, the hypersaline lake, Big Pond, Bahamas and in labo¬ratory experiments. The two fundamentally different natural systems allowed us to compare the geochemical conditions and microbial metabolisms, necessary for car¬bonate formation in microbial mats. Although carbonates are oversaturated in both environments, precipitation does not occur on physicochemical substrates (i.e. out¬side the microbial mats). In the Sarine a high crystal nucleation threshold exceeds the carbonate saturation, despite the high carbonate alkalinity in the water column. Cyanobacterial photosynthesis strongly locally enhances the carbonate alkalinity, whereas the EOM attract and immobilize calcium, which increases the saturation state and finally leads to carbonate precipitation within the EOM (in this case the cyanobacterial sheath) as nucleation template. In Big Pond, the presence of calcium- chelating anions (i.e. sulfate) and EOM, as well as the presence of magnesium, lowers the calcium activity in the water column and mat, and thus inhibits carbonate pre¬cipitation. Coupled with other heterotrophic metabolisms, sulfate reduction uses the EOM as carbon source, degrading it. The resulting EOM consumption creates alkalin¬ity, releases calcium and consumes sulfate in mat-micro domains, which leads to the formation of carbonate layers at the top of the microbial mat. Résumé: Interface biosphère/lithosphère: médiation microbienne de la précipitation de CaC03 dans des environnements en eaux douces et hypersalines Les tapis microbiens engendrent une circulation très efficace des éléments, tels que C, 0, N, S et H, ce qui en fait des acteurs clé pour les processus d'oxydoréduction à l'inter¬face biosphère-lithosphère. Ils sont caractérisés par des taux élevés d'activité méta¬bolique, ainsi que par la production et la consommation de biomasse, principalement constituée de cellules microbiennes et de matière organique extracellulaire (MOE). Dans un tapis microbien, les cellules microbiennes sont enveloppées par une matrice de MOE qui a différentes fonctions dont l'attachement du tapis aux surfaces, la créa¬tion de micro-domaines dans le tapis, la stabilisation physique en situation de stress hydrodynamique, et la protection des cellules dans de multiples autres conditions de stress. La MOE se compose principalement de polysaccharides, d'acides aminés, et d'une variété de groupes fonctionnels chimiques (par exemple, COOH, -SH et -OH). Ces groupes se lient fortement aux cations, tels que Ca2+ et Mg2+, et exercent ainsi un contrôle fort sur la formation de CaC03 dans le tapis microbien. Un mécanisme de rétroaction, entre les métabolismes de la communauté microbienne, leurs produits, et le microenvironnement physico-chimique, influence le degré de saturation de car¬bonate, favorisant soit leur précipitation, soit leur dissolution. Nous avons étudié le moteur et les mécanismes de minéralisation dans des tapis de la Sarine, FR, Suisse et du lac hypersalin, Big Pond, aux Bahamas, ainsi que durant des expériences en laboratoire. Les deux systèmes naturels, fondamentalement dif¬férents, nous ont permis de comparer les conditions géochimiques et les métabolis¬mes nécessaires à la formation des carbonates dans des tapis microbiens. Bien que les carbonates soient sursaturés dans les deux environnements, la précipitation ne se produit pas sur des substrats physico-chimiques (en dehors du tapis microbien). Dans la Sarine, malgré un taux d'alcalinité élevé, les valeurs de seuil pour la nucléa- tion de carbonates sont plus hautes que la saturation du carbonate. La photosynthèse cyanobactérienne augmente localement l'alcalinité, alors que la MOE attire et immo¬bilise le calcium, ce qui augmente l'état de saturation et conduit finalement à la pré¬cipitation des carbonates, en utilisant la MOE comme substrat de nucléation. À Big Pond, la présence de chélateurs de calcium, notamment les anions (p.ex. le sulfate) et la MOE, ainsi que la présence de magnésium, réduit l'activité du calcium et inhibe en conséquence la précipitation des carbonates. Couplée avec d'autres métabolismes hétérotrophes, la réduction des sulfates utilise la MOE comme source de carbone, en la dégradant. Cette consommation de MOE crée l'alcalinité, consomme des sulfates et libère du calcium dans des micro-domaines, conduisant à la formation de couches de carbonates dans le haut du tapis microbien.

Évaluation de la qualité des sites internet francophones traitant de la dépendance à l'alcool

L'objectif de cet article est d'investiguer de manière systématique la qualité des sites internet francophones traitant de la dépendance à l'alcool. Les auteurs ont examiné les 20 premières pages identifiées par trois moteurs de recherche généraux avec deux mots clés. Au total, 45 sites pertinents ont été évalués. Les auteurs concluent que la qualité globale des sites est relativement pauvre, spécialement pour la description des traitements possibles, et largement variable. La qualité de contenu n'est pas corrélée avec les autres aspects évalués tels que l'interactivité, l'esthétisme ou le dévoilement de l'identité des auteurs ou de leur source.

The contribution of the young Cretaceous Caribbean Oceanic Plateau to the genesis of late Cretaceous arc magmatism in the Cordillera Occidental of Ecuador

The eastern part of the Cordillera Occidental of Ecuador comprises thick buoyant oceanic plateaus associated with island-arc tholeiites and subduction-related calc-alkaline series, accreted to the Ecuadorian Continental Margin from Late Cretaceous to Eocene times. One of these plateau sequences, the Guaranda Oceanic Plateau is considered as remnant of the Caribbean-Colombian Oceanic Province (CCOP) accreted to the Ecuadorian Margin in the Maastrichtien. Samples studied in this paper were taken from four cross-sections through two arc-sequences in the northern part of the Cordillera Occidental of Ecuador, dated as (Rio Cala) or ascribed to (Macuchi) the Late Cretaceous and one arc-like sequence in the Chogon-Colonche Cordillera (Las Orquideas). These three island-arcs can clearly be identified and rest conformably on the CCOP. In all four localities, basalts with abundant large clinopyroxene phenocrysts can be found, mimicking a picritic or ankaramitic facies. This mineralogical particularity, although not uncommon in island arc lavas, hints at a contribution of the CCOP in the genesis of these island arc rocks. The complete petrological and geochemical study of these rocks reveals that some have a primitive island-arc nature (MgO values range from 6 to 11 wt.%). Studied samples display marked Nb, Ta and Ti negative anomalies relative to the adjacent elements in the spidergrams characteristic of subductionrelated magmatism. These rocks are LREE-enriched and their clinopyroxenes show a tholeiitic affinity (FeO(1)-TiO(2) enrichment and CaO depletion from core to rim within a single crystal). The four sampled cross-sections through the island-arc sequences display homogeneous initial Nd, and Pb isotope ratios that suggest a unique mantellic source for these rocks resulting from the mixing of three components: an East-Pacific MORB end-member, an enriched pelagic sediment component, and a HIMU component carried by the CCOP. Indeed, the ankaramite and Mg-basalt sequences that form part of the Caribbean-Colombian Oceanic Plateau are radiogenically enriched in (206)Pb/(204)Pb and (207)Pb/(204)Pb and contain a HIMU component similar to that observed in the Gorgona basalts and Galapagos lavas. The subduction zone that generated the Late Cretaceous arcs occurred far from the continental margin, in an oceanic environment. This implies that no terrigenous detrital sediments interacted with the source at this period. Thus, the enriched component can only result from the melting of subducted pelagic sediments. We have thus defined the East-Pacific MORB, enriched (cherts, pelagic sediments) and HIMU components in an attempt to constrain and model the genesis of the studied island-arc magmatism, using a compilation of carefully selected isotopic data from literature according to rock age and paleogeographic location at the time of arc edification. Tripolar mixing models reveal that proportions of 12-15 wt.% of the HIMU component, 7-15 wt.% of the pelagic sediment end-member and 70-75 wt.% of an East-pacific MORB end-member are needed to explain the measured isotope ratios. These surprisingly high proportions of the HIMU/CCOP component could be explained by the young age of the oceanic plateau (5-15 Ma) during the Late Cretaceous arc emplacement. The CCOP, basement of these arc sequences, was probably still hot and easily assimilated at the island-arc lava source. (C) 2008 Elsevier Ltd. All rights reserved,

Synthesis of polyhydroxyalkanoate in the peroxisome of Pichia pastoris.

Polyhydroxyalkanoates (PHAs) are polyesters naturally produced by bacteria that have properties of biodegradable plastics and elastomers. A PHA synthase from Pseudomonas aeruginosa modified at the carboxy-end for peroxisomal targeting was transformed in Pichia pastoris. The PHA synthase was expressed under the control of the promoter of the P. pastoris acyl-CoA oxidase gene. Synthesis of up to 1% medium-chain-length PHA per g dry weight was dependent on both the expression of the PHA synthase and the presence of oleic acid in the medium. PHA accumulated as inclusions within the peroxisomes. P. pastoris could be used as a model system to study how peroxisomal metabolism needs to be modified to increase PHA production in other eukaryotes, such as plants.

"Actes de Paul" et Actes canoniques: un phénomène de relecture

Une approche littéraire de l'intertextualité, à l'aide des catégories posées par G. Genette, permet de renouveler l'approche du rapport entre Actes de Paul et Actes canoniques. A la différence de la critique littéraire classique, qui ne repère pas de dépendance littéraire hors de similitudes verbales ou narratives, l'« hypertextualité » désigne un phénomène de relecture dans lequel un texte-source est recomposé et réinterprété au sein d'un écrit second. Grâce à cette catégorie, cette contribution rend compte du jeu dialectique de parenté et de divergence que l'on observe entre les Actes de Paul et les Actes de Luc. La recomposition de la biographie de Paul dans les Actes de Paul a usé de créativité, elle a puisé dans l'imaginaire chrétien, mais elle s'est aussi servie de traditions préservées dans la suivance de l'apôtre.

The Prenatal Lausanne Trilogue Play: A New Observational Assessment Tool of the Prenatal Co-Parenting Alliance

The goal of this study is to present a new observational assessment tool, the prenatal Lausanne Trilogue Play situation (LTP). Expectant parents were asked to role play their first meeting with their baby using a doll, and the videotaped interaction was subsequently coded. Scores were correlated with measures of the couples' marital satisfaction as well as the postnatal family alliance 3 months after the baby's birth. Results showed that the prenatal co-parenting alliance was positively linked to both fathers' marital satisfaction as well as to the postnatal family alliance at 3 months. Thus, the prenatal LTP allows for assessment of the prenatal co-parenting alliance at the interactional level. It predicts the place the parents will afford their baby after birth and can contribute to methods of clinical assessment and prevention.

Clonal deletion of V beta 14-bearing T cells in mice transgenic for mammary tumour virus.

Autoreactive T lymphocytes are clonally deleted during maturation in the thymus. Deletion of T cells expressing particular receptor V beta elements is controlled by poorly defined autosomal dominant genes. A gene has now been identified by expression of transgenes in mice which causes deletion of V beta 14+ T cells. The gene lies in the open reading frame of the long terminal repeat of the mouse mammary tumour virus.

The Relevance of Long-Term Adherence to Non Pharmacological and Pharmacological Treatment of Hypertension

Current hypertension guidelines point to the necessity of achieving sustained and strict blood pressure control in every hypertensive patient. To reach this goal the patient should comply both with hygienic measures and pharmacologic treatment. This remains a difficult task, particularly since hypertension is generally asymptomatic and since any therapeutic intervention might adversely alter the patient's quality of life. Long-term persistence with antihypertensive therapy is facilated when the treatment is initiated with well tolerated antihypertensive agents, especially blockers of the renin-angiotensin system. Having a normal blood pressure during treatment is also an important determinant of persistence. This explains the growing interest for fixed-dose combinations, which have the main advantage to be at the same time efficient and well tolerated. These simple to use preparations have even gained acceptance as first-line drug regimen.

Descriptive epidemiology of isolated anal anomalies: a survey of 4.6 million births in Europe.

The prevalence of anal anomalies among 4,618,840 births recorded in 33 EUROCAT registries between 1980 and 1994 was 4.05 per 10,000 births. Of the 1,846 recorded cases, 672 (36.4%) were isolated anal anomalies while 1,174 (63.6%) occurred together with other anomalies. Only isolated anal anomalies were analyzed in this study: 75.5% were atresias, 10.1% of which were above and 89.9% were below the level of the levator ani muscle. Fistula occurred in 53% of supralevator and 37% of infralevator atresia. Other anal anomalies were ectopic anus (3.4%), congenital anal fistula (14.7%), and persistent cloaca (0.9%). There was a predominance of males in anal atresia without fistula (male to female (M:F) ratio was 6.7 for supralevator and 2.3 for infralevator atresia), but no significant sex difference in atresias with fistula. There was a predominance of females in ectopic anus and congenital anal fistula (M:F = 0.11 and 0.36 respectively). High frequencies of fetal deaths were recorded in supralevator atresia without fistula (8.3%) and in persistent cloaca (11.1%). Mean gestational length and mean birth weights were reduced for persistent cloaca but were within normal limits for other isolated anal anomalies. Odds ratios (ORs) for mothers above 35 years were increased for supralevator atresia without fistula, supralevator atresia with fistula, and congenital anal fistula. ORs for mothers below 30 years were slightly increased for supralevator atresia without fistula and decreased for persistent cloaca. There were marked differences in prevalence and distribution of anal anomalies among the EUROCAT registries. The results indicated that there are epidemiological differences among the various types of anal anomalies which might reflect different embryological origins.

Couple conjugal et couple co-parental: quelle articulation lors de la transition à la parentalité ?

La venue d'un premier enfant implique d'importants remaniements. Le couple conjugal est mis à rude épreuve et la littérature anglo-saxonne fait état d'une baisse de la satisfaction conjugale durant la période de transition à la parentalité. De plus, au couple conjugal s'ajoutent le couple co-parental (relations entre les parents à propos de leur enfant) et les dyades parentales (parent/enfant). L'articulation entre les sous-systèmes conjugal, co-parental et parental va varier d'une famille à l'autre : prépondérance du parental ou du conjugal, présence d'un co-parentage soutenant ou non, etc. La baisse de la satisfaction conjugale lors de la transition à la parentalité est confirmée dans une étude réalisée en Suisse et présentée dans cet article. Des vignettes cliniques de jeux familiaux illustrent ensuite les différentes articulations possibles du conjugal, du co-parental et du familial. The birth of a first child implies important reorganizations. The marital relationship is under stress and Anglo-Saxon literature shows that there is a decrease of the marital satisfaction during the transition to parenthood. Moreover, when partners become parents, coparenting (relationship between the parents regarding their child) and parental dyads (parent-infant) are added to the marital relationship. The articulation between the conjugal, coparental and parental sub-systems varies from one family to the other : preponderance of the parental or the conjugal subsystem, presence of a supportive co-parenting or not, etc. The decrease of the marital satisfaction during the transition to parenthood is confirmed in a Swiss study and described in this article. Descriptions of family games illustrate then the different possible articulations of the conjugal, coparental and parental subsystems.