The Ionian Sea in southern Italy is at the center of active interaction and convergence between the Eurasian and African–Adriatic plates in the Mediterranean. This area is seismically active with ...instrumentally and/or historically recorded Mw>7.0 earthquakes, and it is affected by recently discovered long strike-slip faults across the active Calabrian accretionary wedge. Many mud volcanoes occur on top of the wedge. A recently discovered one (called the Bortoluzzi Mud Volcano or BMV) was surveyed during the Seismofaults 2017 cruise (May 2017). High-resolution bathymetric backscatter surveys, seismic reflection profiles, geochemical and earthquake data, and a gravity core are used here to geologically, geochemically, and geophysically characterize this structure. The BMV is a circular feature ≃22 m high and ≃1100 m in diameter with steep slopes (up to a dip of 22∘). It sits atop the Calabrian accretionary wedge and a system of flower-like oblique-slip faults that are probably seismically active as demonstrated by earthquake hypocentral and focal data. Geochemistry of water samples from the seawater column on top of the BMV shows a significant contamination of the bottom waters from saline (evaporite-type) CH4-dominated crustal-derived fluids similar to the fluids collected from a mud volcano located on the Calabria mainland over the same accretionary wedge. These results attest to the occurrence of open crustal pathways for fluids through the BMV down to at least the Messinian evaporites at about −3000 m. This evidence is also substantiated by helium isotope ratios and by comparison and contrast with different geochemical data from three seawater columns located over other active faults in the Ionian Sea area. One conclusion is that the BMV may be useful for tracking the seismic cycle of active faults through geochemical monitoring. Due to the widespread diffusion of mud volcanoes in seismically active settings, this study contributes to indicating a future path for the use of mud volcanoes in the monitoring and mitigation of natural hazards.
Abcès hépatiques Rossi, G.; Lafont, E.; Gasperini, L. ...
La revue de medecine interne,
December 2016, 2016-12-00, Letnik:
37, Številka:
12
Journal Article
Recenzirano
Les abcès hépatiques sont des affections rares et graves, dont l’incidence augmente ces dernières années en raison du vieillissement de la population, de l’avènement de la chirurgie pancréatique et ...hépatobiliaire en cancérologie et en transplantation, et de l’augmentation des facteurs d’immunodépression. Le tableau clinique étant très aspécifique, le diagnostic repose principalement sur l’imagerie et sur la ponction diagnostique. Le traitement est mal codifié, mais repose sur l’association d’une antibiothérapie prolongée, et d’un drainage.
Liver abscess is a rare and severe infection. Incidence increases because of aging of population, advances in liver and biliary surgery including liver transplantation, and immunodeficiency factors. Diagnosis depends mainly on imaging and needle aspiration for microbiological identification. Treatment is based on antibiotics, percutaneous or surgical drainage, and control of the primary source.
A 20-Myr record of creation of oceanic lithosphere is exposed along a segment of the central Mid-Atlantic Ridge on an uplifted sliver of lithosphere. The degree of melting of the mantle that is ...upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of approximately 3-4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the mantle is upwelling at an average rate of approximately 25 mm x yr(-1), but this appears to vary through time. Slow-spreading lithosphere seems to form through dynamic pulses of mantle upwelling and melting, leading not only to along-axis segmentation but also to across-axis structural variability. Also, the central Mid-Atlantic Ridge appears to have become steadily hotter over the past 20 Myr, possibly owing to north-south mantle flow.
The long-term successful use of synthetic seismograms in traditional seismic reflection studies suggests that their implementation for high-resolution non-impulsive seismic sources would also be ...beneficial. We present here
ChirCor v1.0, a program for managing physical-log data (P-wave velocity and density) and chirp-sonar seismograms, also equipped with a synthetic-trace generator, that could be used for correlating real seismograms to synthetics. The software, designed with a user-friendly graphic interface, is intended mainly for oceanographers and marine geologists as a tool for correlating high-resolution seismic images and sediment cores.
ChirCor v1.0 will be distributed as freeware for non-commercial purposes. We provide instructions regarding the use of the program together with a description of the algorithms implemented in the code; we also include an example of how to operate with the program based on the data collected during the MARMARA2001 marine geological expedition.
A morphobathymetric survey has been carried out of a coastal lagoon south of the modern Po delta (Valle Fattibello, Comacchio). Acquisition of bathymetric data in such an extremely shallow water ...environment (more than 80% of the area lies between 0 and -1 m) faces technical difficulties that led to the development of 'ad hoc' solutions. Methods to obtain morphobathymetric and reflectivity maps of the lagoon are presented, including descriptions of data acquisition and processing. 'Ground-truthing' of the reflectivity data, provided by analysis of sediment samples, allowed description of the sediment distribution within the lagoon, and the imaging of sedimentary features. Combined analysis of morphobathymetry and reflectivity maps identified arcuate, sand-rich features not in equilibrium with the present-day 'low energy' regime of the lagoon. These features might constitute the substratum over which the lagoon system has been formed, not completely overprinted by anthropogenic and biogeochemical processes at the lagoon bottom. The system we have developed could be used on board remote-controlled or autonomous vehicles that could perform rapid, low-cost surveys and collect data useful for quantitative estimates of sedimentary dynamics. Rapidity and low-cost are important conditions for carrying out periodical surveys, and taking a series of 'snapshots' of the lagoon bottom. This would allow predictive geological models on sediment budgets of these complex environments, characterized by multiple sediment sources and sinks that are difficult to quantify.PUBLICATION ABSTRACT
The catastrophic rupture of the North Anatolian Fault east of the Marmara Sea on 17 August 1999 highlighted a need for mapping the underwater extension of that continental transform. A new ...bathymetric map of Izmit Gulf indicates that the fault follows the axis of the gulf with a few minor bends. Submerged shorelines and shelf breaks that formed during the Last Glacial Maximum provide markers to quantify vertical deformation. Variable tilting of these horizons reveals that vertical deformation is highest just south of the fault. A correlation between vertical deformation of the southern fault block and distance to fault bends can be accounted for by a fault dipping steeply to the south. Hence subsidence (uplift) of the southern, hanging wall block would be expected where the fault strikes at a slightly transtensional (transpressional) orientation to relative plate motion. Subsidence reaches about 8 mm/yr west of the town of Golcuk and might be accommodated in 1–2 m subsidence events during large earthquakes. That scenario is compatible with the tsunami runups and the coseismic subsidence of the southern shore that occurred in 1999. Seafloor morphology also suggests that earthquakes are accompanied by widespread gas and fluid release. The periphery of the deepest basin displays a hummocky texture diagnostic of sediment fluidization, and mud volcanoes occur west of Hersek peninsula that might be activated by earthquakes. Finally, the backscatter imagery reveals a series of lineaments midway through the gulf that are interpreted as products of the 1999 surface rupture. The seafloor is undisturbed farther west, suggesting that surface slip decreased to an insignificant level beyond Hersek. Possibly, the stress shadow from the 10 July 1894 earthquake, which was felt strongly along the western Izmit Gulf, contributed to arrest the 1999 surface rupture.
The Vema Transverse Ridge (VTR) is a prominent, long and narrow topographic anomaly that runs for over 300 km along a sea floor spreading flow line south of the Vema transform at 11° N in the ...Atlantic. It rises abruptly about 140 km from the axis of the Mid-Atlantic Ridge (MAR) in ∼10 Myr old crust and runs continuously up to ∼25 Myr old crust. It reaches over 3 km above the predicted lithospheric thermal contraction level. It is absent in crust younger than 10 Myr; thus, the uplift of the VTR must have ended roughly 10 Ma. The VTR is interpreted as the exposed edge of a flexured and uplifted slab of oceanic lithosphere that was generated at an 80 km long MAR segment. Based on satellite gravimetry imagery this MAR segment was born roughly 50 Ma and increased its length at an average rate of 1.6 mm/yr. Multibeam data show that the MAR-parallel sea floor fabric south of the VTR shifts its orientation by 5° to 10° clockwise in ∼11–12 Myr old crust, indicating a change at that time of the orientation of the MAR axis and of the position of the Euler rotation pole. This change caused extension normal to the transform, followed between 12 and 10 Ma by flexure of the edge of the lithospheric slab, uplift of the VTR at a rate of 2 to 4 mm/yr, and exposure of a lithospheric section (Vema Lithospheric Section or VLS) at the northern edge of the slab, parallel to the Vema transform. Ages of pelagic carbonates encrusting ultramafic rocks sampled at the base of the VLS at different distances from the MAR axis suggest that the entire VTR rose vertically as a single block within the active transform offset. A 50 km long portion of the crest of the VTR rose above sea level, subsided, was truncated at sea level and covered by a carbonate platform. Subaerial and submarine erosion has gradually removed material from the top of the VTR and has modified its slopes. Spreading half rate of the crust south of the transform decreased from 17.2 mm/yr between 26 and 19 Ma to ∼16.9 mm/yr between 19 and ∼10 Ma, to ∼13.6 mm/yr from 10 Ma to present. The slowing down of spreading occurred close in time to the change in ridge/transform geometry, suggesting that the two events are related. A numerical model relates lithospheric flexure to extension normal to the transform, suggesting that the extent of the uplift depends on the thickness of the brittle layer, consistent with the observed greater uplift of the older lithosphere along the VTR.
Objectives: The possibility of cells encapsulation in a polymeric bead with proper characteristics offer many advantages for clinical applications in tissue repair since it is possible to tailor ...these beads for a controlled release of entrapped cells on a repair site. The objective of this study is to evaluate the possibility to use an electro hydro dynamic (EHD) system as a mean to encapsulate living mammalian cells in alginate based hydro-gels. Methods: Capsules are manufactured starting from a tailored algtnate-based liquid solution containing mammalian cells, drops are formed through a needle by a EHD system and these drops are immediately cross-linked In a calcium based solution. The effect of the process on cell viability is assessed and confocal microscopy images will be presented. Results: EHD seems a versatile technique to encapsulate living cells. It allows the creation with high throughput of round beads up to 100um in which cells remain viable starting from solutions characterized by a wide range of viscosity. The viscosity of the solution has an impact on the ability of forming and detaching drops from the EHD needle and as such on their final geometry, while the cross-linker properties determine the morphological characteristics of the final capsules. Conclusions: If the encapsulation of a given cell line is desired, it is important to know what are the ranges of the parameters that characterized the encapsulation process which can be used in order to obtain beads with desired geometry containing viable cells for a specific application.
Hypercalcemia is a rare metabolic disorder in course of B cell lymphoma. The mechanism of hypercalcemia in patients with malignancy may include the increased extrarenal production of vitamin D from ...tumoral cells or neighboring macrophages, i-PTH or PTHrP from tumoral cells. In this case we reported a 34 years old caucasian woman with acute renal failure and hypercalcemia as onset of splenic lymphoma in absence of abnormal levels of serum vitamin D and PTHrP. Because of dramatic recovery of renal function and hypercalcemia after splenectomy, we can speculate that main mechanism of hypercalcemia is related to vitamin D production from neighboring lymphoma macrophages.
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