Laws of distribution of the snow cover on the greater Caucasus (Soviet Union)

The laws of the distribution of the snow cover on the mountains of the greater Caucasus are discussed. It is shown that an extremely unequal distribution of the snow cover is caused by the complex orography of this territory, the diversity of climatic conditions and by the difference in altitude. Regions of constant, variable and unstable snow cover are distinguished because of the clearly marked division into altitude layers, each of which is characterized by climatic differences in the nature of the snow accumulation

Approach to Evaluating Characteristics of Multichannel Loss System with FCFD Preempted Priority Discipline

In the paper we consider a multichannel loss preemptive priority system with a Poisson input and general service time distribution depending on the priority of job. Jobs of the same priority are preempted according with First Come First Displaced (FCFD) protocol. Approximate formulas are obtained for the loss probability of a prescribed priority job and some other characteristics of the system. It particular cases, the obtained formulas are exact.Comment: 6 pages, no figures. arXiv admin note: text overlap with arXiv:2206.0926

Laser-induced persistent photovoltage on the surface of a ternary topological insulator at room temperature

Using time- and angle-resolved photoemission, we investigate the ultrafast response of excited electrons in the ternary topological insulator (Bi$_{1 x}$Sb$_{x}$)$_2$Te$_3$ to fs-infrared pulses. We demonstrate that at the critical concentration $x$=0.55, where the system becomes bulk insulating, a surface voltage can be driven at room temperature through the topological surface state solely by optical means. We further show that such a photovoltage persists over a time scale that exceeds $\sim$6 $\mu$s, i.e, much longer than the characteristic relaxation times of bulk states. We attribute the origin of the photovoltage to a laser-induced band-bending effect which emerges near the surface region on ultrafast time scales. The photovoltage is also accompanied by a remarkable increase in the relaxation times of excited states as compared to undoped topological insulators. Our findings are relevant in the context of applications of topological surface states in future optical devices.Comment: 5 pages, 4 figure

Metaphysics of Labor in Russian Culture: Part One

The article tries to describe a complex phenomenon in Russian culture and philosophy - the metaphysics of labor.  Much attention is paid to Russian philosophical thought of the beginning of the 20th century, and the views of L.N. Tolstoy to this problem.  The question is raised about the formation of economic and labor ethics in Russia, as well as the religious motivation of work. The axiological value of labor for the Russian person is determined, the metaphysical essence of labor in the national image of the world is revealed.  This was still discussed by religious thinkers.  S.N. Bulgakov wrote about the "sophisticated" nature of labor activity.  The study also examines the phenomenon of laziness, the category of "leisure", "free time" in the context of spiritual Russian culture.  The connection of labor activity with moral categories is traced.  The work involves analytical, historical, descriptive and systematic methods of analysis

Ultrafast spin polarization control of Dirac fermions in topological insulators

Three-dimensional topological insulators (TIs) are characterized by spin-polarized Dirac-cone surface states that are protected from backscattering by time-reversal symmetry. Control of the spin polarization of topological surface states (TSSs) using femtosecond light pulses opens novel perspectives for the generation and manipulation of dissipationless surface spin currents on ultrafast timescales. Using time-, spin-, and angle-resolved spectroscopy, we directly monitor for the first time the ultrafast response of the spin polarization of photoexcited TSSs to circularly-polarized femtosecond pulses of infrared light. We achieve all-optical switching of the transient out-of-plane spin polarization, which relaxes in about 1.2 ps. Our observations establish the feasibility of ultrafast optical control of spin-polarized Dirac fermions in TIs and pave the way for novel optospintronic applications at ultimate speeds.Comment: 9 pages, 4 figure

Trigonal-bipyramidal Anion [Ph2Cl3Sn]- in the Structure of N-[(Diethylphosphoryl)methyl] piperidinium Diphenyltrichlorostannate(IV)

Crystal structure of N-(diethylphosphoryl)methyl-piperidinium diphenyltrichlorostannate(IV), C10H23NO3P+ C12H10Cl3Sn- has been determined, a = 11.416(2), b = 11.582(2), c = 12.491(2) Å, α = 69.82(2), β = 81.22(2), γ = 60.73(2)°, space group P1̅, 4493 reflections, R(F) = 0.0271, wR(F2) = 0.0712. The structure consists of isolated trigonal-bipyramidal anions and hydrogen-bonded dimers formed by cations. The impact of secondary Sn⋅⋅⋅Cl interactions on the geometry of complex anions is discussed

Angle-closure glaucoma, iris-lens contact, ciliochoroidal effusion, and transient myopia induced by topiramate

Topiramate is a sulphonamide derivative indicated in the treatment of epilepsy and migraine. In foreign scientific literature there are reported cases of topiramate-induced bilateral angle-closure glaucoma and acute myopia with ciliochoroidal effusion.Purpose. To evaluate outcomes of laser iridectomy in a patient with topiramate-induced angle-closure glaucoma and acute myopia with ciliochoroidal effusion.Material and methods. A case is reported of bilateral angle-closure glaucoma, iris-lens contact, ciliochoroidal detachment and acute myopia following topiramate for migraine treatment in a 32-year-old patient. Laser peripheral iridectomy was performed in the both eyes according to the standard technology (Nd:YAG laser Selecta Trio, Lumenis Ltd., Israel) to decrease IOP and restore visual functions.Results. After laser iridectomy, the examination showed normal IOP with no medication, ciliochoroidal effusion and induced myopic shift were relieved.Conclusion. Laser iridectomy is an effective and safe in the treatment of topiramate-induced angle-closure glaucoma, acute myopia, and ciliochoroidal detachment. It contributes to normalization of IOP and improvement of visual acuity