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Abstract: The article presents data on the morphology, range, and number of the American mink in Yakutia, gives materials on its morpho- and craniometry. Data on the dynamics of the range and number of the American mink in Yakutia from the moment of its introduction in the early 1960s to the present time are shown. The range of the mink has expanded in the northeast direction from Southern Yakutia to Central Yakutia for half a century, and new mink settlement sites on the eastern side of Yakutia from Magadan Region have been noted. After naturalization of the American mink for 25 years, there was a gradual increase in its number from 686 individuals to 4000–5000 individuals. Over the next 35 years, the number of the species stabilized and has remained at this level with some fluctuations over the years, excluding 2005–2006, when there was a sharp increase in the number of mink.

Abstract—: The article proposes an approach to determining the volume of domestic tourism in Russia and evaluates its dynamics from 2009 to 2020. Based on the use of intersectoral modeling, the economic effects of a twofold increase in the number of trips across the country planned by 2035 are determined. To achieve this indicator, a number of measures are required to increase tourist consumption within the country. In conclusion, directions are formulated that contribute to the activation of demand for domestic tourism.

Anti-angiogenic therapies for cancer such as VEGF neutralizing antibody bevacizumab have limited durability. While mechanisms of resistance remain undefined, it is likely that acquired resistance to anti-angiogenic therapy will involve alterations of the tumor microenvironment. We confirmed increased tumor-associated macrophages in bevacizumab-resistant glioblastoma patient specimens and two novel glioblastoma xenograft models of bevacizumab resistance. Microarray analysis suggested downregulated macrophage migration inhibitory factor (MIF) to be the most pertinent mediator of increased macrophages. Bevacizumab-resistant patient glioblastomas and both novel xenograft models of resistance had less MIF than bevacizumab-naive tumors, and harbored more M2/protumoral macrophages that specifically localized to the tumor edge. Xenografts expressing MIF-shRNA grew more rapidly with greater angiogenesis and had macrophages localizing to the tumor edge which were more prevalent and proliferative, and displayed M2 polarization, whereas bevacizumab-resistant xenografts transduced to upregulate MIF exhibited the opposite changes. Bone marrow-derived macrophage were polarized to an M2 phenotype in the presence of condition-media derived from bevacizumab-resistant xenograft-derived cells, while recombinant MIF drove M1 polarization. Media from macrophages exposed to bevacizumab-resistant tumor cell conditioned media increased glioma cell proliferation compared with media from macrophages exposed to bevacizumab-responsive tumor cell media, suggesting that macrophage polarization in bevacizumab-resistant xenografts is the source of their aggressive biology and results from a secreted factor. Two mechanisms of bevacizumab-induced MIF reduction were identified: (1) bevacizumab bound MIF and blocked MIF-induced M1 polarization of macrophages; and (2) VEGF increased glioma MIF production in a VEGFR2-dependent manner, suggesting that bevacizumab-induced VEGF depletion would downregulate MIF. Site-directed biopsies revealed enriched MIF and VEGF at the enhancing edge in bevacizumab-naive patients. This MIF enrichment was lost in bevacizumab-resistant glioblastomas, driving a tumor edge M1-to-M2 transition. Thus, bevacizumab resistance is driven by reduced MIF at the tumor edge causing proliferative expansion of M2 macrophages, which in turn promotes tumor growth.

Context. In 2003, the Sun and the Earth passed through both the equatorial plane of Jupiter and therefore the orbital planes of its main satellites. Aims. During this period, mutual eclipses and occultations were observed and we present the data collected.Methods. Light curves of mutual eclipses and occultations were recorded by the observers of the international campaign PHEMU03 organized by the Institut de m?canique c?leste, Paris, France. Results. We completed 377?observations of 118?mutual events from 42?sites and the corresponding data are presented in this paper. For each observation, information about the telescope, receptor, site, and observational conditions are provided.Conclusions. This paper gathers all data and indicates a first estimate of its precision. This catalogue of these rare events should constitute an improved basis for accurate astrometric data useful in the development of dynamical models.

We present the results of photometric observations of Saturn's seventh satellite Hyperion and four other planetary satellites: Saturn's moon Phoebe and three Jovian satellites Himalia, Elara, and Pasiphae. The observations have been conducted from September, 1999 to March, 2000, and during September–October, 2000. Analysis of periodic variations in Hyperion's lightcurve was performed. The lightcurve was modeled using the software package developed for calculating the rotational dynamics of a satellite. Our data generally indicate that over the period of observations Hyperion was in the chaotic mode of rotation.

Using the integral operator that defines a solution of the Cauchy problem for the equation $$L_n u = \square ^n u + a_1 \square ^{n - 1} u + \cdot \cdot \cdot + a_n u = f(x,y),$$ we find an integral representation for solutions of the equation $$(\square + k)^n u = f(x,y)$$ in terms of arbitrary functions that are continuously differentiable sufficiently many times.

Abstract: We construct differential operators Kg(z), Lg(z), $$Kg(z),\;Lg(z),\,\,M\overline {f(z)} ,$$ , and $$N\overline {f(z)} $$ such that they map arbitrary holomorphic functions in a simply connected domain D in the complex plane z=x+iy into regular solutions of the equation

Structural changes of (111)Si after 10keV D+2 ion implantation with fluence in the range of 1016 - 1019 cm-2 at room temperature have been studied with cross-sectional transmission electron microscopy (XTEM), secondary ion mass spectroscopy (SIMS) and neutral molecules mass spectroscopy (NMMS).Three stages of structural, as well as chemical evolution is observed. For fluence less than (3-4) · 1016cm-2 deuterium retains in the target through trapping on the dangling bonds with SiD-complexes formation. This process results in formation of the strongly damaged region. As the fluence is increased the buried amorphous layer on the depth close to Rd appears. Simultaneously generating of SiD2-complexes begins. The nucleation and incorporation of SiD2-complexes leads to a network of voids creation. For fluence higher than 1018 cm-2 the erosional relief at the target surface is formed due to effective sputtering of the amorphous material with voids.

Recurrence relations are obtained for problems of optimal filtration and interpolation of partially observed discrete Markov chains. We present the system of differential equations for problems of optimal nonlinear filtration for Markov processes with continuous time and the system of inverse differential equations for problems of optimal nonlinear interpolation.

Conclusions The gear-type vacuum press of the design developed, in which the feeder and the pressing device are made in the form of gears in contact engagement, is suitable for operation with mixtures of reduced moisture content and for production of thin walled parts of complex profile.

Effect of repeated ultrasonic impact treatment on redistribution of residual stresses in a dissimilar thickness girth butt weld of pipes with a diameter of 530 mm of low alloyed (0.9%C-2%Mn-1%Si) steel was studied. Residual stresses were measured by the X-ray method based on measurement of microdeformation of a crystal lattice of a material under its influence. The research results showed that tensile residual stresses in the girth weld were formed at the inner side of the pipe after welding. Ultrasonic impact treatment of the weld at the inner side caused complete transformation of residual stresses from tensile to compressive ones when speed was in the range from 0.06 to 0.12 m/min. However, reduce in speed of treatment down to 0.04 m/min gave a negative effect. The values of compressive residual stresses in heat affected zone on the side of the thinner pipe were decreased.