Impact of external medium conductivity on cell membrane electropermeabilization by microsecond and nanosecond electric pulses

The impact of external medium conductivity on the efficiency of the reversible permeabilisation caused by pulsed electric fields was investigated. Pulses of 12 ns, 102 ns or 100 μs were investigated. Whenever permeabilisation could be detected after the delivery of one single pulse, media of lower conductivity induced more efficient reversible permeabilisation and thus independently of the medium composition. Effect of medium conductivity can however be hidden by some saturation effects, for example when pulses are cumulated (use of trains of 8 pulses) or when the detection method is not sensitive enough. This explains the contradicting results that can be found in the literature. The new data are complementary to those of one of our previous study in which an opposite effect of the conductivity was highlighted. It stresses that the conductivity of the medium influences the reversible permeabilization by several ways. Moreover, these results clearly indicate that electropermeabilisation does not linearly depend on the energy delivered to the cells

Formation of xenon-nitrogen compounds at high pressure

Molecular nitrogen exhibits one of the strongest known interatomic bonds, while xenon possesses a closed-shell electronic structure: a direct consequence of which renders both chemically unreactive. Through a series of optical spectroscopy and x-ray diffraction experiments, we demonstrate the formation of a novel van der Waals compound formed from binary Xe-N2 mixtures at pressures as low as 5 GPa. At 300 K and 5 GPa Xe(N$_2$)$_2$-I is synthesised, and if further compressed, undergoes a transition to a tetragonal Xe(N$_2$)$_2$-II phase at 14 GPa; this phase appears to be unexpectedly stable at least up to 180 GPa even after heating to above 2000 K. Raman spectroscopy measurements indicate a distinct weakening of the intramolecular bond of the nitrogen molecule above 60 GPa, while transmission measurements in the visible and mid-infrared regime suggest the metallisation of the compound at ~100 GPa

Biorefinery of the macroalgae Ulva lactuca: extraction of proteins and carbohydrates by mild disintegration

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Research data supporting "Synthesis and stability of xenon oxides Xe2O5 and Xe3O2 under pressure"

Crystallographic information files of structures in the Xe-O binary system predicted to be stable at high pressures (83 GPa, 150 GPa and 200 GPa). Pressures and space groups given in file names. Structures found using Ab Initio Random Structure Searching (AIRSS) coupled with Density Functional Theory (DFT) methods.This work was supported by the EPSRC [research grant numbers EP/J017639/1 and EP/K014560/1], European Synchrotron Radiation Facility [grant numbers HS-4067 and HC-767] and Royal Society Wolfson Research Merit Award (for Chris J. Pickard)