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The article examines the possibilities of applying interdisciplinary connections in learning English during the teaching of socio-humanitarian disciplines for students of the specialty «Sociology». The author gives an example of his own development of an individual assignment based on the implementation of the principle of interdisciplinarity in the educational process, which contributes to the improvement of English-language professional communication among students of non-philological specialties. The obtained results represent individual work as an effective tool for the formation of general and professional competences of applicants for higher education, as well as the development of their foreign language communicative competence, which significantly increases the competitiveness of modern specialists.

Spectral and photometric monitoring of CTTS RY Tau in 2013-2021 revealed variations in the H-alphaand NaID lines at radial velocities of infall (accretion) and out ow (wind) with a period of about 22 days. The NaID absorption in the infalling and out owing gas changes in anti-phase: an increase in the density of infalling gas is accompanied by a decrease in the wind density, and vice versa. The fluctuations remain coherent for several years of observation. We assume that the observed effect may be due to processes at the disk-magnetosphere boundary in MHD propeller mode. The stability of the oscillation phase indicates the possible presence of a massive planet, causing azimuthal asymmetry of the accretion and wind flows. If the observed period (22 days) is Keplerian, then the planet is located at a distance of 0.2 AU and moves with an orbital velocity of 100 km s-1.

Planets are thought to form at the early stage of stellar evolution when mass accretion is still ongoing. RY Tau is a T Tauri type star at the age of a few Myr, with an accretion disc seen at high inclination, so that the line of sight crosses both the wind and accretion gas flows. In a long series of spectroscopic monitoring of the star over the period 2013-2020, we detected variations in H$\, {\alpha }$ and Na i D absorptions at radial velocities of infall (accretion) and outflow (wind) with a period of about 22 d. The absorptions in the infalling and outflowing gas streams vary in antiphase: an increase of infall is accompanied by a decrease of outflow, and vice versa. These 'flip-flop' oscillations retain phase over several years of observations. We suggest that this may result from the magnetohydrodynamics processes at the disc-magnetosphere boundary in the propeller mode. Another possibility is that a massive planet is modulating some processes in the disc and is providing the observed effects. The period, if Keplerian, corresponds to a distance of 0.2 au, which is close to the dust sublimation radius in this star. The presence of the putative planet can be confirmed by radial velocity measurements: the expected amplitude is ≥90 m s-1 if the planet mass is ≥2 MJ. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.

Характеризуются основные задачи и функции туристического страноведения. Рассматриваются проблемы содержания учебного туристического страноведения, его соотношения с другими дисциплинами цикла подготовки специалистов в сфере туризма и гостеприимства. Artemenko S. V. Tasks and Functions of Tourism Geography. Characterized by the main tasks and functions of tourism geography. The problems of the content of educational tourism geography, its relationship with other disciplines cycle of training in the field of tourism and hospitality.

We study theoretically the electron transport in a 1D conductor adiabatically connected to a superconducting and normal metal leads. In the case of non-interacting we show that ac voltage applied along with dc voltage modifies I-V curve resembling a regime of photon-assisted tunneling. We obtain in the limit of low voltages, that the electron-electron interaction affects electronic transport resulting in a decrease of conductance and features in the frequency dependence of the impedance., This paper has been withdrawn by the author due to a crucial error in equations (38)-(39)

We discuss optical absorption in topological insulators and study possible photoelectric effects theoretically. We found that absorption of circularly polarized electromagnetic waves in two-dimensional topological insulators results in electric current in the conducting 1D edge channels, the direction of the current being determined by the light polarization. We suggest two ways of inducing such a current: due to magnetic dipole electron transitions stimulated by irradiation of frequency below the bulk energy gap, and due to electric dipole transitions in the bulk at frequencies larger than the energy gap with subsequent capture of the photogenerated carriers on conducting edge states., Comment: 5 pages, 2 figures

Long-term, uniform series of UBVR observations of T Tauri and Herbig Ae stars obtained over 20 yr at the Maidanak Observatory as part of the ROTOR program are analyzed. We find a linear relationship between the characteristic variability time scale and the bolometric luminosity of the star+disk system: the higher the luminosity, the slower the brightness variations. This dependence is valid over a wide range of masses and luminosities, from T Tauri stars to Herbig Ae stars. On average, the variability time scale is one-quarter the Keplerian period at the dust-sublimation radius, which is known from interferometric observations. Some T Tauri stars have periods from 25 to 120 days, which are preserved over several observing seasons. These periods correspond to Keplerian orbits with semi-major axes from 0.14 to 0.52 AU. The results obtained provide indirect evidence for the existence of protoplanets in the gas-dust disks of stars in early stages of their evolution toward the main sequence.

Renormalization of the Coulomb interaction in layered metals results in a strongly anisotropic plasma mode with low frequencies for small components of wave vector in the in-plane direction. Interaction of electrons with this mode was found to lead to an incoherent contribution to the electron spectral density which spreads up to large energies. In the superconducting state this reproduces the peak-dip-hump feature similar to that observed in layered high-T$_c$ superconductors. The incoherent part of the spectral density and plasmon-assisted electron transitions provide mechanisms for nearly linear conductivity in the stack direction at large voltages or frequencies., 4 pages, 1 figure

The mechanism of conductivityin the regime of the intrinsic Josephson effect is studied in layered superconductors with singlet d-wave pairing. The cases of coherent and incoherent interlayer tunneling of electrons are considered. The theory with coherent tunnelling describes main qualitative features of the effect observed in highly anisotropic high-Tc superconductors at voltages smaller than the amplitude of the superconducting gap, the mechanism of resistivity being related to the excitations of quasiparticles via the d-wave gap. Interaction of the Josephson junctions formed by the superconducting layers due to the charging effects is shown to be small., Proučavaju se mehanizmi vodljivosti u uvjetima intrinsičnog Josephsonovog efekta u slojevitim supravodičima sa singletnim d-valnim sparivanjem. Razmatraju se slučajevi koherentnog i nekoherentnog međuslojnog tuneliranja elektrona. Teorija s koherentnim tuneliranjem opisuje glavne kvalitativne značajke efekta koji se opaža u jako anizotropnim visokotemperaturnim supravodičima, na naponima manjim od supravodljivog procijepa, za koji se otpornost svodi na uzbudu kvazičestica putem d-valnog procijepa. Pokazuje se da je međudjelovanje Josephsonovih spojeva medu supravodljivim slojevima, koje je posljedica učinaka nabijanja, malo.

In the frame of an exactly solvable model we calculate electric and magnetic fields created by uniformly moving lattice of Josephson vortices driven by the transport current in the magnetic field parallel to conducting layers. The distribution of fields and currents is strongly modified at large velocities of the vortex lattice, plasma oscillations of superconducting electrons being excited by flux flow at low temperatures. This modifies the flux flow resistivity and results in interference features in I-V curves, thus regions of negative differential conductivity appear in which the uniform motion of the vortex lattice is not stable. The spectrum of electromagnetic radiation by moving vortices contains large peaks related to the excitation of plasma oscillations and to the Cherenkov radiation., Comment: 7 pages, 2 postscript figures, Latex

In the recent paper Ohashi and Takada (OT) made statements that in the clean limit considered by us (AV) in 1975, weakly damped collective oscillations in superconductors do not exist due to the Landau damping and their spectrum differs from that obtained in AV. In this Comment we would like to note that these statements arise as a result of a misunderstanding of the term "clean" case. OT considered the limit of frequencies larger, than elastic scattering rate, meanwhile AV obtained weakly damped mode in the case when temperature is larger than scattering rate, the frequencies being smaller (!) than elastic scattering rate. All these problems were discussed in our review article in 1979 which was, presumably, unknown to OT., 4 pages, no figures, Latex