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A crucial issue in the development of therapies to treat pathologies of the central nervous system is represented by the availability of non-invasive methods to study the threedimensional morphology of spinal cord, with a resolution able to characterize its complex vascular and neuronal organization. X-ray phase contrast micro-tomography enables a highquality, 3D visualization of both the vascular and neuronal network simultaneously without the need of contrast agents, destructive sample preparations or sectioning. Until now, high resolution investigations of the post-mortem spinal cord in murine models have mostly been performed in spinal cords removed from the spinal canal. We present here post-mortem phase contrast micro-tomography images reconstructed using advanced computational tools to obtain high-resolution and high-contrast 3D images of the fixed spinal cord without removing the bones and preserving the richness of micro-details available when measuring exposed spinal cords. We believe that it represents a significant step toward the in-vivo application. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

A crucial issue in the development of therapies to treat pathologies of the central nervous system is represented by the availability of non-invasive methods to study the threedimensional morphology of spinal cord, with a resolution able to characterize its complex vascular and neuronal organization. X-ray phase contrast micro-tomography enables a highquality, 3D visualization of both the vascular and neuronal network simultaneously without the need of contrast agents, destructive sample preparations or sectioning. Until now, high resolution investigations of the post-mortem spinal cord in murine models have mostly been performed in spinal cords removed from the spinal canal. We present here post-mortem phase contrast micro-tomography images reconstructed using advanced computational tools to obtain high-resolution and high-contrast 3D images of the fixed spinal cord without removing the bones and preserving the richness of micro-details available when measuring exposed spinal cords. We believe that it represents a significant step toward the in-vivo application. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Condensation of model chromatin in the form of fully saturated 12-mer nucleosome arrays, induced by addition of cationic ligands (ε-oligolysines with charge varied from +4 to +11), was studied in a range of KCl concentrations (10-500mM) using light scattering and precipitation assay titrations. The dependence of EC50 (ligand concentration at the midpoint of the array condensation) on CKCl displays two regimes, a salt-independent at low CKCl and a salt-dependent at higher salt concentrations. In the salt-dependent regime EC50 rises sharply with increase of CKCl. Increase of ligand charge shifts the transition from the salt-independent to salt-dependent regime to higher salt. In the nucleosome array system, due to the partial neutralization of the DNA charge by histones, a lower oligocation concentration is needed to provoke condensation in the salt-independent regime compared to the related case of DNA condensation by the same cation. In the physiological range of salt concentrations (CKCl=50-300mM), K+ ions assist array condensation by shifting EC50 of the ε-oligolysines to lower values. At higher CKCl, K+ competes with the cationic ligands, which leads to increase of EC50. Values of salt-dependent dissociation constant for the ε-oligolysine-nucleosome array interaction were obtained, by fitting to a general equation developed earlier for DNA, describing the dependence of EC50 on dissociation constant, salt and polyelectrolyte concentrations. © 2011 Elsevier Inc.

In light–matter interfaces based on the Faraday effect, quite a number of quantum information protocols have been successfully demonstrated. In order to further increase the performance and fidelities achieved in these protocols, a deeper understanding of the relevant noise and decoherence processes needs to be gained. In this paper, we provide for the first time a complete description of the decoherence from spontaneous emission. We derive from first principles the effects of photons being spontaneously emitted into unobserved modes. Our results relate the resulting decay and noise terms in effective equations of motion for collective atomic spins and the forward-propagating light modes to the full atomic level structure. We illustrate and apply our results to the case of a quantum memory protocol. Our results can be applied to any alkali atoms, and the general approach taken in this paper can be applied to light–matter interfaces and quantum memories based on different mechanisms.

In light–matter interfaces based on the Faraday effect, quite a number of quantum information protocols have been successfully demonstrated. In order to further increase the performance and fidelities achieved in these protocols, a deeper understanding of the relevant noise and decoherence processes needs to be gained. In this paper, we provide for the first time a complete description of the decoherence from spontaneous emission. We derive from first principles the effects of photons being spontaneously emitted into unobserved modes. Our results relate the resulting decay and noise terms in effective equations of motion for collective atomic spins and the forward-propagating light modes to the full atomic level structure. We illustrate and apply our results to the case of a quantum memory protocol. Our results can be applied to any alkali atoms, and the general approach taken in this paper can be applied to light–matter interfaces and quantum memories based on different mechanisms.

Samples of pure Ti were oxidized at 800-1200C in an air atm. After cooling in air the sample was cut in 2 pieces; 1 part was used for hardness measurement of the layer saturated with gas, the 2nd one for emission spectral analysis with the help of electrical discharge. TiN and TiC were used as standards. Direct proportionality between the intensity of the spectral line and N concn. was assumed for the range of 0-22.6%. Results of the hardness measurement were in good agreement with the spectral data. (Author), Edited trans. of mono. Voprosy Analiticheskoi Zhimii Mineralnykh Veshchestv (Analytical Chemical Studies in Mineral Materials) Leningrad, 1966 p88-94.

Contents: Allowance for backscattering of a laser beam along inclined trajectories; Inclusions in neodymium glasses., Edited trans. of Optiko-Mekhanicheskaya Promyshlennost (USSR) v35 n2 p6-10, 38-41 1968, by E. Harter.