The Gulf of Lions in the northwestern Mediterranean is one of the few sites around the world ocean exhibiting deep open‐ocean convection. Based on 6 year long (2009–2015) time series from a mooring ...in the convection region, shipborne measurements from repeated cruises, from 2012 to 2015, and glider measurements, we report evidence of bottom thick nepheloid layer formation, which is coincident with deep sediment resuspension induced by bottom‐reaching convection events. This bottom nepheloid layer, which presents a maximum thickness of more than 2000 m in the center of the convection region, probably results from the action of cyclonic eddies that are formed during the convection period and can persist within their core while they travel through the basin. The residence time of this bottom nepheloid layer appears to be less than a year. In situ measurements of suspended particle size further indicate that the bottom nepheloid layer is primarily composed of aggregates between 100 and 1000 µm in diameter, probably constituted of fine silts. Bottom‐reaching open ocean convection, as well as deep dense shelf water cascading that occurred concurrently some years, lead to recurring deep sediments resuspension episodes. They are key mechanisms that control the concentration and characteristics of the suspended particulate matter in the basin, and in turn affect the bathypelagic biological activity.
Key Points
Six years record of temperature, current, turbidity, and bioluminescence in the convection zone of the northwestern Mediterranean
Strong currents associated to bottom‐reaching convection induce deep sediment resuspension and formation of aggregates in the water column
Upward transfer of resuspended sediment, stimulated by eddy activity, produces thick, and long‐lasting bottom nepheloid layers
Using X-ray diffraction experiments and curvature measurements, in-situ real-time measurements of stress are performed during solid state reaction of a palladium thin film with Si(001). From X-ray ...diffraction measurements and using the sin
2
ψ method, we found out that the stress in the metal and in the silicide is compressive. This stress decreases all along the solid-state reaction for the silicide. We then compared our results with the qualitative model proposed by Zhang and d’Heurle. This model suggests the development of a high compressive stress (−2.4 GPa) in the silicide.
Experiments were performed on thick GaInAs and GaAsN layers and on GaInAs quantum wells grown on
(1
1
1)
B
and
(0
0
1)
GaAs substrates. The aim of this work is to develop an experimental procedure in ...order to evaluate the chemical compositions and relaxation state of the samples at global as well as nanometre scale. Chemical analyses (EDS, RBS, etc.), X-ray diffraction (reciprocal space map, sin
2
ψ, etc.) and XTEM were carried out.
The validity of the sin
2
ψ method on the above mentioned thin layers has been tested. Good accuracy is obtained for In and N composition but more work has to be done in order to optimize the determination of the relaxation state. Coupling TEM observations to these calculations gives valuable information on the relaxation mechanisms (misfit dislocations, stacking faults, microtwins, etc.).
(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Atmospheric neutrinos are produced during cascades initiated by the interaction of primary cosmic rays with air nuclei. In ...this paper, a measurement of the atmospheric ... energy spectrum in the energy range 0.1-200 TeV is presented, using data collected by the ANTARES underwater neutrino telescope from 2008 to 2011. Overall, the measured flux is 25 % higher than predicted by the conventional neutrino flux, and compatible with the measurements reported in ice. The flux is compatible with a single power-law dependence with spectral index γ ^sub meas^=3.58±0.12. With the present statistics the contribution of prompt neutrinos cannot be established.
Progressive inhibition of cholinesterases by organophosphates results from phosphorylation of the active-site serine. Phosphorylated cholinesterases may undergo a dealkylation reaction of the ...organophosphorus moiety leading to "aged" enzyme, i.e. conversion of the inhibited enzyme into a non-reactivable form. Aging occurs rapidly when the inhibitor is soman, a powerful nerve agent. This reaction promotes formation of a salt bridge between the protonated histidine of the active site catalytic triad and a negatively charged oxygen bound to the phosphorus atom. This reaction is accompanied by enzyme conformational and stability changes. In the research of compounds which retard or prevent the dealkylation reaction of organophosphate-cholinesterase conjugates, some allosteric effectors are relatively efficient by decreasing the velocity of the "aging" process. Knowledge of the three-dimensional structure of non-inhibited, inhibited and aged cholinesterases allows to understand the intimate mechanism of irreversible enzyme inhibition. Modeling of enzyme structure in the presence of effectors is essential to find out new therapeutic means against organophosphate poisoning.
Subzero temperature gradient gel electrophoresis is a new approach which allows to measure the transition temperature of low temperature-induced subtle conformational changes of proteins and to ...detect the different conformational states, including unfolded states. Using this technique under destabilizing conditions, i.e., in the presence of 4 M urea, bovine pancreas ribonuclease A exhibited two transitions: (i) a continuous transition with a midpoint temperature of -14 degrees C corresponding to a rapid equilibrium between the initial enzyme state and a conformational state more compact than the initial one; (ii) a discontinuous transition at -22.5 degrees C from intermediate to a non migrating species. Under reducing conditions this second transition was shifted toward high temperatures (-18.5 degrees C). We attempted to detect these two transitions by differential scanning calorimetry, UV spectrophotometry and circular dichroism measurements. These transitions have been ascribed to subtle cold-induced conformational changes.
This paper reports a search for spatial clustering of the arrival directions of high energy muon neutrinos detected by the ANTARES neutrino telescope. An improved two-point correlation method is used ...to study the autocorrelation of 3058 neutrino candidate events as well as cross-correlations with other classes of astrophysical objects: sources of high energy gamma rays, massive black holes and nearby galaxies. No significant deviations from the isotropic distribution of arrival directions expected from atmospheric backgrounds are observed.
A search for cosmic neutrino sources using six years of data collected by the ANTARES neutrino telescope has been performed. Clusters of muon neutrinos over the expected atmospheric background have ...been looked for. No clear signal has been found. The most signal-like accumulation of events is located at equatorial coordinates RA=\(-\)46.8\(^{\circ}\) and Dec=\(-\)64.9\(^{\circ}\) and corresponds to a 2.2\(\sigma\) background fluctuation. In addition, upper limits on the flux normalization of an E\(^{-2}\) muon neutrino energy spectrum have been set for 50 pre-selected astrophysical objects. Finally, motivated by an accumulation of 7 events relatively close to the Galactic Centre in the recently reported neutrino sample of the IceCube telescope, a search for point sources in a broad region around this accumulation has been carried out. No indication of a neutrino signal has been found in the ANTARES data and upper limits on the flux normalization of an E\(^{-2}\) energy spectrum of neutrinos from point sources in that region have been set. The 90% confidence level upper limits on the muon neutrino flux normalization vary between 3.5 and 5.1\(\times\)10\(^{-8}\) GeV\(\,\)cm\(^{-2}\)s\(^{-1}\), depending on the exact location of the source.
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