Contourite depositional system after the exit of a strait: Case study from the late Miocene South Rifian Corridor, Morocco

Idealized facies of bottom current deposits (contourites) have been established for fine-grained contourite drifts in modern deep-marine sedimentary environments. Their equivalent facies in the ancient record however are only scarcely recognized due to the weathered nature of most fine-grained deposits in outcrop. Facies related to the erosional elements (i.e. contourite channels) of contourite depositional systems have not yet been properly established and related deposits in outcrop appear non-existent. To better understand the sedimentary facies and facies sequences of contourites, the upper Miocene contourite depositional systems of the South Rifian Corridor (Morocco) is investigated. This contourite depositional system formed by the dense palaeo-Mediterranean Outflow Water. Foraminifera assemblages were used for age-constraints (7.51 to 7.35 Ma) and to determine the continental slope depositional domains. Nine sedimentary facies have been recognized based on lithology, grain-size, sedimentary structures and biogenic structures. These facies were subsequently grouped into five facies associations related to the main interpreted depositional processes (hemipelagic settling, contour currents and gravity flows). The vertical sedimentary facies succession records the tectonically induced, southward migration of the contourite depositional systems and the intermittent behaviour of the palaeo-Mediterranean Outflow Water, which is mainly driven by precession and millennial-scale climate variations. Tides substantially modulated the palaeo-Mediterranean Outflow Water on a sub-annual scale. This work shows exceptional examples of muddy and sandy contourite deposits in outcrop by which a facies distribution model from the proximal continental slope, the contourite channel to its adjacent contourite drift, is proposed. This model serves as a reference for contourite recognition both in modern environments and the ancient record. Furthermore, by establishing the hydrodynamics of overflow behaviour a framework is provided that improves process-based interpretation of deep-water bottom current deposits

Sedimentary processes and glacial cycles on the sediment drifts of the Antarctic Peninsula Pacific margin: preliminary results of SEDANO-II Project

6nonenoneLUCCHI R.G; REBESCO M; BUSETTI M; CABURLOTTO A; COLIZZA E.; FONTOLAN GLUCCHI R., G; Rebesco, M; Busetti, M; Caburlotto, A; Colizza, Ester; Fontolan, Giorgi

Occurrence and genetic diversity of Arcobacter butzleri in an artisanal dairy plant in Italy

The present study aimed to investigate the presence, distribution and persistence of Arcobacter spp. in an artisanal dairy plant, and to test the isolates to determine different genotypes in the processing plant and in foods. Samples were collected in an artisanal cheese factory on four occasions between October and December 2012: food samples (raw milk, ricotta cheese, mozzarella cheese and conditioning liquid), water samples and environmental samples were analyzed by cultural method; isolates were identified by multiplex-PCR and genotyped by PFGE analysis. Arcobacter butzleri was isolated from 29 out of 59 samples (46.6%), 22 from environmental and 7 from food samples respectively; cluster analysis divided the strains into 47 PFGE patterns: 14 PFGE clusters and 33 unique types. Our findings indicate that the plant harbored numerous A. butzleri pulsotypes and that the manual cleaning and sanitation in the studied dairy plant does not effectively remove Arcobacter. The recurrent isolation of A. butzleri suggests that the environmental conditions in the dairy plant constitute a good ecological niche for the colonization of this microorganism. In some cases, the presence of indistinguishable strains isolated from the same facilities on different sampling days showed that these strains were persistent in the processing environment

Occurrence and antibiotici susceptibility of Helicobacter pullorum from turkeys intensively reared in northern italy

There is no data in literature regarding Helicobacter pullorum occurrence in Turkey, therefore from September to December 2006, caecal contents from 55 animals coming from 11 different intensive farms (5.samples/farm) were collected at the slaughterhouse. Gramnegative curved rod bacteria, isolated by a modified Steele-McDermott membrane filter method, were identified as H. pullorum using two different Polymerase Chain Reaction (PCR) assays based on 16S rRNA and on gyrA gene. One isolate from each farm was randomly selected and subjected to phenotypic characterisation by biochemical methods and 1D SDS-PAGE analysis of whole cell proteins, and to Minimum Inhibitory Concentration (MIC) for seven different antibiotics by agar dilution method. According to the PCRs results, 42 (76.4%) out of 55 animals examined were positive for H. pullorum and 100% of farms resulted infected. The 1D SDS-PAGE whole protein profile analysis showed a high similarity among 11 isolates tested and the type strain of H. pullorum. A monomodal distribution for the MIC values was found for ampicillin (2–32 lg/ml), chloramphenicol (4–32 lg/ml), gentamicin (0.25–0.5 lg/ml) and nalidixic acid (8–128 lg/ml), while a bimodal trend was observed for erythromycin (MICs range 2–8 lg/ml and ‡ 256 lg/ml), ciprofloxacin (0.25–0.5 lg/ml and 16–128 lg/ml) and tetracycline (1–4 lg/ml and 128 ‡ 256 lg/ml) indicating a probable acquired resistance. This is the first report of isolation and characterisation of H. pullorum from Turkey. The occurrence and antibiotic susceptibility of H. pullorum observed in turkeys resulted similar to previous descriptions of this microorganism in broiler chickens and laying hens in Italy. The detection of a high number of colonies phenotypically similar to H. pullorum , in the first isolation plates, suggests that this micro-organism, when present, colonizes the caecum of Turkey at a high concentration

Mud volcanoes along the inner deformation front of the Calabrian Arc accretionary wedge (Ionian Sea)

We present geophysical data integrated with the analysis of well-targeted sediment samples in order to contribute to a better understanding of fluid circulation in the Calabrian Arc accretionary wedge. Two cores (BS81/II 5 and BS81/II 10) collected on a swell in the hangingwall of the inner deformation front show upper Pleistocene mud breccias that include Cretaceous to Late Miocene rock fragments mechanically incorporated into the eruption deposit by the upward transport of overpressured fluids. An additional core (CALA 21) came from the summit of a topographic high in the footwall of the inner deformation front of the accretionary wedge and contains a mud breccia patchy/cloudy facies where sediment disturbance is caused by fluid expulsion. Integration of the entire data set provides evidences of the interplay among tectonics, fluid emissions and sedimentation, and enables the identification of two new volcanoes in the accretionary prism where overpressuring due to Pliocene and Pleistocene sediment accumulation and the evolution of active fault systems triggered fluid circulation and the formation of those structures

Occurrence of Helicobacter pullorum in turkeys

The present investigation was undertaken to identify and characterize the tetracycline resistance determinant in 22 Gallibacterium anatis strains for which no determinant was identified using primers specific for tet(A, B, C, D, E, G, H, K, L, M, O). A recent study found tet(B) to be themost prevalent tetracycline resistance determinant in a larger collection of G. anatis field strains from Mexico and Denmark. However, in 41% of the tetracycline resistant strains no determinant could be assigned. Here we demonstrate that tet(31) is a common determinant in G. anatis originating from chickens from very different production systems and localities. In addition, tet(31) was identified in strains isolated over a 30-year period. This is the first report on tet(31) since its original identification in Aeromonas salmonicid

Modern sedimentation patterns and human impacts on the Barcelona continental shelf (NE Spain)

Seafloor sediments were collected from the Barcelona continental shelf, NE Spain, to determine the textural characteristics and sedimentary processes related to different depositional systems and human pressures. The Barcelona continental shelf is principally influenced by the discharge of the Llobregat and Besòs rivers, and also by anthropogenic modifications Duch as the diversion of the Llobregat River or the enlargement of the Port of Barcelona. Sedimentological, physical and biogeochemical properties of 14 sediment cores and grabs indicate the presence of three distinct depositional environments linked to river-influenced, marine-influenced and mixed sedimentation. Sedimentological results have been used to groundtruth available backscatter data. The river-influenced environment, mainly associated to the Llobregat River input, does not reach the shelf edge as the prevailing oceanographic currents deflect sediments south-westward. Riverine sediments are fine-grained, with abundant plant debris, micas and relatively high organic carbon content. The associated sedimentary features are the Holocene prodelta and two modern mud patches. The marine-influenced environment extends north-easterly over the middle and outer shelf and on the upper continental slope. The sediments are coarser grained with abundant bioclasts and lower organic carbon content. Mixed sedimentation is present between the river- and marine-influenced areas. In addition, 210Pb, 226Ra and 137Cs radiometric analyses were used to estimate accumulation rates as well as to identify sites with disturbed sedimentation. Relatively high sediment accumulation rates (up to 0.70-1.03 g�cm-2�yr-1 equivalent to 6.4-10 mm�yr-1) are estimated on the Llobregat prodelta while moderate rates 0.21-0.46 g�cm-2�yr-1 or 1.6-3.6 mm�yr-1) are found between the Besòs and the Llobregat outlets. Two sediment cores show a sharp change from river-influenced to marine-dominated conditions that occurred in the mid- 1960s. This is interpreted as a significant regression (~2.5 km in 40 years) of the river-influenced domain that may be associated to the extension of the Port of Barcelona and the canalization of the Besòs River, amongst other reasons. Other important human impacts observed in the Barcelona continental shelf are (i) sediment mixing by dredging, ship anchoring and trawling; and (ii) possible organic pollution associated to river and sewage discharges