RÉSUMÉ
One of Saturn's largest moons, Enceladus, possesses a vast extraterrestrial ocean (i.e., exo-ocean) that is increasingly becoming the hotspot of future research initiatives dedicated to the exploration of putative life. Here, a new bio-exploration concept design for Enceladus' exo-ocean is proposed, focusing on the potential presence of organisms across a wide range of sizes (i.e., from uni- to multicellular and animal-like), according to state-of-the-art sensor and robotic platform technologies used in terrestrial deep-sea research. In particular, we focus on combined direct and indirect life-detection capabilities, based on optoacoustic imaging and passive acoustics, as well as molecular approaches. Such biologically oriented sampling can be accompanied by concomitant geochemical and oceanographic measurements to provide data relevant to exo-ocean exploration and understanding. Finally, we describe how this multidisciplinary monitoring approach is currently enabled in terrestrial oceans through cabled (fixed) observatories and their related mobile multiparametric platforms (i.e., Autonomous Underwater and Remotely Operated Vehicles, as well as crawlers, rovers, and biomimetic robots) and how their modified design can be used for exo-ocean exploration.
Sujet(s)
Exobiologie/instrumentation , Environnement extraterrestre , Techniques photoacoustiques/instrumentation , Saturne , Conception d'appareillage , Exobiologie/méthodes , Océans et mers , Robotique/instrumentationRÉSUMÉ
Acoustic noise levels were measured in the Gulf of Catania (Ionian Sea) from July 2012 to May 2013 by a low frequency (<1000Hz) hydrophone, installed on board the NEMO-SN1 multidisciplinary observatory. NEMO-SN1 is a cabled node of EMSO-ERIC, which was deployed at a water depth of 2100m, 25km off Catania. The study area is characterized by the proximity of mid-size harbors and shipping lanes. Measured noise levels were correlated with the passage of ships tracked with a dedicated AIS antenna. Noise power was measured in the frequency range between 10Hz and 1000Hz. Experimental data were compared with the results of a fast numerical model based on AIS data to evaluate the contribution of shipping noise in six consecutive 1/3 octave frequency bands, including the 1/3 octave frequency bands centered at 63Hz and 125Hz, indicated by the Marine Strategy Framework Directive (2008/56/EC).
Sujet(s)
Surveillance de l'environnement , Bruit , Navires , Acoustique , EauRÉSUMÉ
Abyssal temperature and velocity observations performed within the framework of the Neutrino Mediterranean Observatory, a project devoted to constructing a km(3)-scale underwater telescope for the detection of high-energy cosmic neutrinos, demonstrate cross-fertilization between subnuclear physics and experimental oceanography. Here we use data collected south of Sicily in the Ionian abyssal plain of the Eastern Mediterranean (EM) basin to show for the first time that abyssal vortices exist in the EM, at depths exceeding 2,500 m. The eddies consist of chains of near-inertially pulsating mesoscale cyclones/anticyclones. They are embedded in an abyssal current flowing towards North-Northwest. The paucity of existing data does not allow for an unambiguous determination of the vortex origin. A local generation mechanism seems probable, but a remote genesis cannot be excluded a priori. The presence of such eddies adds further complexity to the discussion of structure and evolution of water masses in the EM.
RÉSUMÉ
Kinetic energies of light fragments ( A=10) from the decay of target spectators in 197Au+197Au collisions at 1000 MeV per nucleon have been measured with high-resolution telescopes at backward angles. Except for protons and apart from the observed evaporation components, the kinetic-energy spectra exhibit slope temperatures of about 17 MeV, independent of the particle species, but not corresponding to the thermal or chemical degrees of freedom at breakup. It is suggested that these slope temperatures may reflect the intrinsic Fermi motion and thus the bulk density of the spectator system at the instant of becoming unstable.
RÉSUMÉ
Scleroderma is a chronic disease of unknown origin characterized by diffuse sclerosis of the connective tissue of the integument and other organs. As in systemic lupus erythematosus (SLE), rheumatoid arthritis and dermatomyositis, a variety of antibodies may be found in the serum, suggesting that immune mechanisms may be involved. In two uremic patients with scleroderma, the effects were studied of the removal, by pheresis, of antinuclear antibodies, immune complexes, and immunoglobulin factors perpetuating the inflammatory response. We used a membrane plasmapheresis with a hollow-fiber type plasmafilter (Plasmaflo, Asahi) connected online with a hemofilter for conventional dialysis. The aim of this preliminary study was to induce a remission of the edematous inflammatory phase. The correlation of a improvement in clinical response and a decrease in the levels of immune complexes or other factors of inflammation was observed. In our view membrane-plasmapheresis is a process safely carried out by the hemodialysis staff and it may be of clinical effectiveness, especially, in patients with life-threatening complications of progressive systemic sclerosis.