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In this research, combined effect of chlorin e6 and noninvasive 20 kHz, low-powered ultrasound on melanoma cells is proposed for the first time. The proposed combination incorporates the application of safe low-frequency ultrasound that is used for transdermal drug delivery. We demonstrate that impact of the 20 kHz ultrasound on chlorin e6 leads to strong sonodynamic effect in melanoma cells. We also show that chlorin e6 keeps its monomeric form in the cells and does not aggregate after exposure to ultrasound. We propose a two-step model where sonoluminescence serves as an internal light source for the chlorin e6 photoactivation., Comment: 26 pages, 8 figures

We report a 51V nuclear magnetic resonance investigation of the frustrated spin-1/2 chain compound LiCuVO4, performed in pulsed magnetic fields and focused on high-field phases up to 55 T. For the crystal orientations H // c and H // b we find a narrow field region just below the magnetic saturation where the local magnetization remains uniform and homogeneous, while its value is field dependent. This behavior is the first microscopic signature of the spin-nematic state, breaking spin-rotation symmetry without generating any transverse dipolar order, and is consistent with theoretical predictions for the LiCuVO4 compound., Comment: Main manuscript (5 pages, 3 figures) and the Supplemental Material (1 page, 2 figures), altogether 6 pages, 5 figures

By measuring the nuclear magnetic resonance (NMR) 1/T_1 relaxation rate in the Br (bond) doped DTN compound, Ni(Cl(1-x)Br_x)2-4SC(NH2)2 (DTNX), we show that the low-energy spin dynamics of its high magnetic field "Bose-glass" regime is dominated by a strong peak of spin fluctuations found at the nearly doping-independent position H* = 13.6 T. From its temperature and field dependence we conclude that this corresponds to a level crossing of the energy levels related to the doping-induced impurity states. Observation of the local NMR signal from the spin adjacent to the doped Br allowed us to fully characterize this impurity state. We have thus quantified a microscopic theoretical model that paves the way to better understanding of the Bose-glass physics in DTNX, as revealed in the related theoretical study [M. Dupont, S. Capponi, and N. Laflorencie, Phys. Rev. Lett. 118, 067204 (2017), arXiv:1610.05136]., Comment: 6 pages, 4 figures