Nature of low-energy excitations in La<Subscript>1.87</Subscript>Sr<Subscript>0.13</Subscript>CuO<Subscript>4</Subscript> superconducting cuprate

The spectra of the conductivity and dielectric constant of La_1.87Sr_0.13CuO₄ cuprate have been directly measured in the frequency range of 0.3 to 1.2 THz (10–40 cm⁻¹) and the temperature range of 5 to 300 K in the E | c polarization (the electric field vector of radiation is perpendicular to the copper-oxygen planes). Excitation has been observed in the superconducting phase, and its nature has been attributed to the transverse optical excitation of the condensate of Cooper pairs, which appears because Josephson junctions between CuO planes are modulated due to in-plane magnetic and charge stripes. Additional quasiparticle absorption of unknown origin has been detected at frequencies below ≈15 cm⁻¹ at liquid helium temperatures.     

Features of diffusion of an incident particle

Mechanisms of turbulent diffusion of particles moving in a turbulent medium under the action of gravity and Stokes forces are studied. It is observed that the velocity variance of particles decreases upon an increase in the inertia of the motion. At the same time, the diffusion coefficients of a particle are independent of its inertia. It is shown that, as the velocity of incidence increases, diffusion in the vertical plane becomes stronger than in the horizontal plane, and the ratio of the horizontal and vertical diffusion coefficients decreases to 1: 2.     

Effects of lipopolysaccharide-induced inflammation on expression of growth-associated genes by corticospinal neurons

Background  

Inflammation around cell bodies of primary sensory neurons and retinal ganglion cells enhances expression of neuronal growth-associated genes and stimulates axonal regeneration. We have asked if inflammation would have similar effects on corticospinal neurons, which normally show little response to spinal cord injury. Lipopolysaccharide (LPS) was applied onto the pial surface of the motor cortex of adult rats with or without concomitant injury of the corticospinal tract at C4. Inflammation around corticospinal tract cell bodies in the motor cortex was assessed by immunohistochemistry for OX42 (a microglia and macrophage marker). Expression of growth-associated genes c-jun, ATF3, SCG10 and GAP-43 was investigated by immunohistochemistry or in situ hybridisation.     

Rate of hydrogenation of vinyl and allyl compounds of carbon,silicon, germanium,and tin on skeletal nickel

Russian Chemical Bulletin - As in radical additions, vinyl compounds of silicon are hydrogenated more rapidly than allyl compounds. Vinyl and allyl double bonds in germanium and tin compounds...     

Stability of circumferentially corrugated shells under hydrostatic pressure

A method to solve stability problems for corrugated shells with dished ends subject to hydrostatic pressure is outlined. Critical loads are determined by solving a boundary-value problem with unknown amplitude of nonaxisymmetric perturbation. It is shown that the shells are highly sensitive to the axial component of hydrostatic pressure     

Initial postbuckling behavior of cylindrical composite shells under axisymmetric deformation

A solution is obtained that describes the postbuckling behavior of cylindrical shells in the case of axisymmetric buckling. The basis for this solution is Koiter’s asymptotic method and the nonlinear equations of the third-order Timoshenko theory of shells. It is shown that the bifurcation point in this case is a symmetrically unstable one. The effect of the initial axisymmetric deflections on the buckling loads is weaker when buckling is axisymmetric. The results obtained by Koiter’s special theory evidence this __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 4, pp. 108–118, April 2006.     

Aspects of the Qualitative Theory of Suspended Foliations

We proved that the set of suspended foliations of a compact manifold M is open in the space of foliations with C r -topology. Relation between sets of suspended foliations with Hausdorff and non-Hausdorff graphs are investigated from topological and set-theoretical points of view. Continuum set of pairwise non-isomorphic C X -diffeomorphisms of 1-dimensional manifold with special properties is constructed and used essentially.     

Investigation of intramolecular mobility of acrylate cation exchangers: The influence of cross-linkage concentration

Relaxation Mössbauer spectra of two⁵⁷Fe³⁺-exchanged acrylate cation-exchangers (SGK-7 and SG-1M, USSR) with various cross-linkage concentrations 2.5–16 mol.% were observed in windows of observation up to 250 mm/s. The frequencies of slow (ω?10 s^?1) intramolecular motions (displayed in Mössbauer lineshape) and the values of high frequency (ω?10 s^?1) atomic displacements (reflected in thef’ factor) decrease with the increase of cross-linkage concentration.     

Conformal pasting on a torus

We solve the problem concerning global conformal pasting on a torus given by the algebraic equation $$u^2 = (1 - z^2 ) (1 - k^z 2^2 ) (0< k< 1).$$ We obtain an algebraic equation for the new torus, and we find the function which accomplishes the conformal pasting.