Regeneration of Cellulose Insulation of Windings of Long-Life Power Transformers

Main aspects of the physicochemical condition of cellulose insulation of windings of power transformers with a long-term service life are analyzed with the aim of determining criteria on the possibility of prolonging the life of the insulation by washing with surface-active substances.     

Heat and mass exchange in an optically thin,turbulent boundary layer in an IR radiation field

The procedure and results of an experimental investigation of the temperature and velocity distribution in a plane, incompressible, turbulent boundary layer of air and of CO₂ in an IR radiation field are presented. Data are given on heat exchange under the conditions of curtain cooling.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 6, pp. 885–894, June, 1985.The authors thank Academician S. S. Kutateladze for support of the work and fruitful discussions.     

Radiant-conductive heat transfer in a plane ammonia layer

Results of experimental and theoretical investigations of radiant-conductive heat transfer in a plane ammonia layer are presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 18, No. 2, pp. 216–223, February, 1970.     

Detecting transition to chatter mode in peakless tool turning by monitoring vibration and acoustic emission signals

Stability of a peakless tool turning on slender shafts was studied under conditions of low- and high-magnitude vibrations by registering and short-time Fourier transformation (STFT) processing of acoustic emission (AE) and vibration acceleration (VA) signals. Both VA and AE signals have been registered in three positions of the cutting tool on the workpiece and for different shaft diameters. Both amplitude- and frequency-dependent AE and VA characteristics were obtained and analyzed for overall process signal length as well as for single frames. It was shown that power spectrum characteristic could be used for monitoring the fast-occurring changes in the cutting process stability. A criterion of the cutting process stability based on the power spectrum has been offered.     

Dual Fermion Approach to High-Temperature Superconductivity

We present an extension of the recently proposed dual fermion approach to investigate the superconducting properties of the Hubbard model in two dimensions. From the spin–spin susceptibility, we find a reduction of the Néel temperature compared to results from dynamical mean-field theory (DMFT) calculations due to the incorporation of spatial correlations. We present results for the temperature dependence of the leading eigenvalue of the Bethe–Salpeter equation for the particle–particle channel. In agreement with previous studies, we find singlet d-wave pairing to be the dominant contribution to pairing. We further present first results for the finite-doping phase diagram obtained from the leading eigenvalue of the Bethe–Salpeter equations for the particle–hole and particle–particle channels.     

Subtype of Neuroblastoma Cells with High KIT Expression Are Dependent on KIT and Its Knockdown Induces Compensatory Activation of Pro-Survival Signaling

Neuroblastoma (NB) is a pediatric cancer with high clinical and molecular heterogeneity, and patients with high-risk tumors have limited treatment options. Receptor tyrosine kinase KIT has been identified as a potential marker of high-risk NB and a promising target for NB treatment. We investigated 19,145 tumor RNA expression and molecular pathway activation profiles for 20 cancer types and detected relatively high levels of KIT expression in NB. Increased KIT expression was associated with activation of cell survival pathways, downregulated apoptosis induction, and cell cycle checkpoint control pathways. KIT knockdown with shRNA encoded by lentiviral vectors in SH-SY5Y cells led to reduced cell proliferation and apoptosis induction up to 50%. Our data suggest that apoptosis induction was caused by mitotic catastrophe, and there was a 2-fold decrease in percentage of G2-M cell cycle phase after KIT knockdown. We found that KIT knockdown in NB cells leads to strong upregulation of other pro-survival growth factor signaling cascades such as EPO, NGF, IL-6, and IGF-1 pathways. NGF, IGF-1 and EPO were able to increase cell proliferation in KIT-depleted cells in an ERK1/2-dependent manner. Overall, we show that KIT is a promising therapeutic target in NB, although such therapy efficiency could be impeded by growth factor signaling activation.