Influence of an Anomalous Temperature Dependence of the Phase Coherence Length on the Conductivity of Magnetic Topological Insulators.

Magnetotransport constitutes a useful probe to understand the interplay between electronic band topology and magnetism in spintronic devices. A recent theory of Lu and Shen [Phys. Rev. Lett. 112, 146601 (2014)PRLTAO0031-900710.1103/PhysRevLett.112.146601] on magnetically doped topological insulators predicts that quantum corrections Δκ to the temperature dependence of conductivity can change sign across the Curie transition. This phenomenon has been attributed to a suppression of the Berry phase of the topological surface states at the Fermi level, caused by a magnetic energy gap. Here, we demonstrate experimentally that Δκ can reverse its sign even when the Berry phase at the Fermi level remains unchanged. The contradictory behavior to theory predictions is resolved by extending the model by Lu and Shen to a nonmonotonic temperature scaling of the inelastic scattering length showing a turning point at the Curie transition.

Multiple-timescale relaxation dynamics in CsGd(MoO4)2--a dipolar magnet with a highly anisotropic layered crystal structure.

The dynamic properties of the dipolar magnet CsGd(MoO4)2 have been studied. The frequency and temperature dependence of the AC susceptibility investigated in the paramagnetic region above 2 K revealed the co-existence of magnetic field induced slow and fast relaxation channels with a timescale differing by three orders of magnitude. The slow relaxation is determined by the properties of the first coordination sphere of the Gd(3+) ion and has the character of a two-phonon Orbach process. The fast relaxation is potentially attributed to a two-phonon Raman process realized via a localized phonon mode associated with the layered crystal structure. The temperature dependence of the phonon mean free path in zero magnetic field indicates significant phonon scattering below 1 K resulting from the combined effect of magnetic correlations and the scattering of dominant phonons with energies corresponding to the crystal-field levels.

Slow spin relaxation induced by magnetic field in [NdCo(bpdo)(H2O)4(CN)6]⋠3H2O.

We report on a comprehensive investigation of the magnetic properties of [NdCo(bpdo)(H2O)4(CN)6]⋅3H2O (bpdo=4, 4'-bipyridine-N,N'-dioxide) by use of electron paramagnetic resonance, magnetization, specific heat and susceptibility measurements. The studied material was identified as a magnet with an effective spin S = 1/2 and a weak exchange interaction J/kB = 25 mK. The ac susceptibility studies conducted at audio frequencies and at temperatures from 1.8 to 9 K revealed that the application of a static magnetic field induces a slow spin relaxation. It is suggested that the relaxation in the magnetic field appears due to an Orbach-like process between the two lowest doublet energy states of the magnetic Nd(3+) ion. The appearance of the slow relaxation in a magnetic field cannot be associated with a resonant phonon trapping. The obtained results suggest that the relaxation is influenced by nuclear spin driven quantum tunnelling which is suppressed by external magnetic field.

[The organization of disability prevention among hypertension patients]. / Organizatsiia profilaktiki invalidnosti u bol'nykh gipertonicheskoi bolezn'iu.

A study was made of the causes and factors that determine disability in 102 able-bodied patients suffering from essential hypertension (a random sample), who were acknowledged invalids for the first time in 1989. Analysis of the shortcomings in the organization of the treatment and prophylactic aid to the population made it possible to outline the main trends in disability prevention in patients suffering from essential hypertension.

[Cancer of the vulva]. / Rak vul'vy.

An analysis of 66 observations of cancer of the external genitalia is presented. This lesion was most frequently observed in patients aged from 51 to 75 (58 observations). Pruritus in the external genitalia region was the predominant symptom (47 cases), a more rare on--the appearance of tumor and pains in the vulva region (27 cases). In 45 females tumor was located in large and small pudendal lips, in 19-in the clitoris, and in 2-in the region of the commissura labiorum posterior. In examination 8 patients showed cancer of the vulva, stage 1, 24-stage II, 31-stage III and 3-stage IV. In 23 patients the combined treatment was employed, which initial step included short-focus roentgenotherapy of the primary tumor and deep x-ray irradiation of regional lymph nodes, 43 patients were subjected only to radiotherapy. An average survival in the patients following the treatment in all stages was 3.47 years. In the combined therapy it was 4.35, in radiotherapy-2.6 years.