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A cross section of the process e+e−→KS0K±π∓π+π− has been measured for the first time using a data sample of 185.4 pb$^{−1}$ collected with the CMD-3 detector at the VEPP-2000 e+e− collider. With the KS0→π+π− decay detection, 373±20 and 514±28 signal events have been selected with six and five reconstructed tracks, respectively, in the center-of-mass energy range 1.6–2.0 GeV. The total systematic uncertainty of the cross section is about 15%. A study of the production dynamics allows us to extract a contribution from the e+e−→f1(1285)π+π− intermediate state and to measure the corresponding cross section. The intermediate states with the f1(1420) and f1(1510) resonances have been observed.

The cross section of the process $e^+e^-\toπ^+π^-$ has been measured in the center of mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on a full dataset collected below 1 GeV during three data taking seasons, corresponding to an integrated luminosity of about 62 pb$^{-1}$. In the dominant $ρ$-resonance region, a systematic uncertainty of 0.7% has been reached. At energies around $ϕ$-resonance the $π^+π^-$ production cross section was measured for the first time with high energy resolution. The forward-backward charge asymmetry in the $π^+π^-$ production has also been measured. It shows the strong deviation from the theoretical prediction based on conventional sQED framework and is in good agreement with GVDM and dispersive-based predictions. The impact of presented results on the evaluation of the hadronic contribution to the anomalous magnetic moment of muon is discussed., 48 pages, 36 figures

Non-separation measurement of a multiphase mixture coming from an oil well is traditionally considered a complex measurement, for which rather expensive solutions are used, including non-trivial maintenance. This work aims to describe a new technology in the area of measuring multiphase oil and gas-water mixture, which is being finalized by specialists of the Tomsk Polytechnic University for conducting pilot tests at the facilities of Zarubezhneft JSC, and to indicate a more informative level of measurement of oil and gas industry production, which allows measuring the amount of oil, gas and water with high precision without the use of radioactive sources and constriction devices. The purpose of measuring a multiphase mixture is to determine the amount of oil, gas and water. In order to do this, it is required to determine the total flow rate of the mixture and the distribution of the flow by substances and phases: oil gas, oil and formation water. The total flow rate in the developed multiphase X-ray flowmeter is based on cross-correlation analysis of radiograms from two linear detectors. Measurement of the component composition for the purpose of the distribution of the flow by substances and phases is carried out by the method of two-wave absorptiometry.

Study of population genetic structure is essential for insight in species biology, but mechanisms of its formation and factors influencing it remain insufficiently understood. Here we analyzed differentiation among populations in small colonial seabird of North Pacific, the Parakeet Auklet Aethia psittacula, which was previously considered as a monomorphic species. We compare our results with data on congeneric species to investigate the most important factors affecting the process of population differentiation in Aethini. We analyzed morphometric measurements, mitochondrial DNA control region fragment and microsatellite loci from six Parakeet Auklet colonies spanning the breeding range. Although results of microsatellite variability analysis did not reveal differences between birds from different colonies, results of control region variability and morphometric analyses testified for a slight but significant differentiation between birds from the Aleutian Islands and other parts of their range. They were significantly smaller in most linear parameters measured and had higher body condition (expressed as the scaled mass index). The results of mtDNA analysis and discrepancy between different types of genetic markers indicated that birds from Aleutian Islands and from the other parts of their breeding range probably originated from different refuges and the differentiation of mitochondrial lineages between them took place around 100 000 years ago. Our results and conclusions from the comparison with congeneric species indicated that foraging and migration patterns seem to determine population structure in small planktivorous alcids, with panmixia in highly mobile species, clear population differentiation in resident species and intermediate population differentiation in more dispersive species.

Despite a great number of empirical studies, the mechanisms of population differentiation and the factors that influence this process, particularly in seabirds, remain insufficiently understood. Here we analyzed population structure in the whiskered auklet Aethia pygmaea, a previously poorly studied alcid species with unusual differentiation in colony attendance rhythms (i.e. diurnal in the Sea of Okhotsk vs nocturnal in the Bering Sea), and examined the influence of it on intraspecific differentiation. For this study, we analyzed morphometric measurements, acoustic variables, mitochondrial control region fragment and five microsatellite loci from nine whiskered auklet colonies spanning the breeding range. Previous research has shown a clinal morphometric variation in this species. We build on this analysis by adding auklets from more colonies, for the first time analyzing vocalizations from different colonies and genetic structure of this species. Our data supports a clinal variation in morphometric and acoustic characters with the largest size and the lowest call frequency in western birds, and the smallest size and highest call frequency in the east. We also found two mitochondrial lineages – whiskered auklets from colonies in the Sea of Okhotsk and the Commander Is. (Bering Sea) and from the Aleutian Is. (Bering Sea), that were presumably formed during Sangamonian interglacial period (115 000–130 000 years ago). Genetic clusters found did not reflect differences in colony attendance rhythms, suggesting that they were shaped by other factors (e.g. differences in predator pressure) and are unlikely to have participated in the formation of population structure. Colony fidelity, mobility of birds, proximity of foraging grounds and location of colonies in relation to seasonal ice pack, seem to be more likely determinants of population differentiation.

The effect of philopatry on the formation of the intrapopulation structure in the crested auklet colony of the Talan Island, Tauiskaya Bay of the Sea of Okhotsk, was examined. The nucleotide sequences of the mitochondrial DNA control region fragment (408 bp) and five microsatellite loci (Apy03, Apy04, Apy06, Apy07, Apy10) in individuals from two study plots of the colony were examined. A high genetic diversity (H = 0.999 ± 0.003) and the absence of intrapopulation genetic differentiation was observed at both types of mark ers. Thus, despite the high level of nest-area fidelity in breeding adults, no genetic isolation was revealed for crested auklets from different parts of the Talan Island colony.

Spectra and field dependencies of Transversal Kerr Effect (TKE) for [(Co45Fe45Zr10)46(Al2O3)54(X)/Si (Y)]nmultilayers (ML) with thin layers (X < 2,5 nm; Y < 3,5 nm) have been studied in the energy range 0,5 – 4,0 eV. It was found that TKE field dependencies in the nearest infrared (IR) and visible energy ranges exhibit anomalous behavior. TKE spectra measured in weak (~30 Oe) and strong (~2 kOe) magnetic fields were essentially different. It was shown that magneto-optical response of multilayered structure composite-silicone is the sum of magnetic composite layers and composites formed on interface contributions. And these contributions may have an opposite sign of TKE. Interface magnetic states depend on composite and semiconductor layers’ thicknesses and FM phase concentration in composite layers.

The study of population differentiation is essential for understanding species evolution and ecology. Despite a large amount of published works in this area of study, the prediction of population structure in a number of animal species and, particularly, in seabirds remains difficult. The Crested Auklet (Aethia cristatella) is a small, planktivorous seabird species that breeds in colonies on islands and along the coastline of the North Pacific. Despite their vast breeding area and huge population numbers, the phenotypic features of adult birds from different colonies and genetic population variability have not been studied yet. Here we conducted a combined study of population differentiation in the Crested Auklet, using both phenotypic and genetic features. Data were collected at nine points across the species’ distribution range from 1988 to 2012. We analyzed population variability of the mitochondrial control region fragment, microsatellites, two types of vocalizations (barks and trumpet calls), morphometric and ornamentation measurements. However, we did not detect any obvious cues to different populations, either in genetic, morphometric or acoustic variables. Crested Auklets from different geographic areas do not express any genetic differences. We surmise that the absence of population separation in Crested Auklet can be explained by an important ecological characteristic of the species: these birds are pelagic during non-breeding season; therefore, young birds likely migrate far away from their natal colonies during their first year of life and do not often return to breed at their native colony.

The article describes the wide range of applications at all stages of development of hydrocarbon deposits mapping method. On the model region – Karachaganak gas condensate field to demonstrate the use of modern geoinformation technologies in creating a series of inventory and assessment of landscape-ecological maps, maps of general scientific content, maps application and purpose.

An efficient two-step procedure “imine formation/azirine–carbenoid coupling” has been developed for the preparation of 1,2-dihydropyrimidines from azirine-2-carbaldehydes, primary amines, and diazo carbonyl compounds under Rh(II) catalysis. The formation of 1,2-dihydropyrimidines involves 100% regioselective addition of the rhodium carbenoid to endocyclic nitrogen atom of the 2H-azirine-2-carbaldimine. According to the DFT calculations the reaction proceeds via dissociation of the metal-bound complex of the azirinium ylide to metal-free azirinium ylide, ring-opening of the latter to give a 1,5-diazahexa-1,3,5-triene, followed by 1,6-cyclization. The 1,2-dihydropyrimidines with two different electron-withdrawing substituents at the C2 position can undergo in solution inversion of configuration of the stereogenic center at C2 via “the N1–C2 bond cleavage/rotation around the N–C single bond/1,6-cyclization” sequence.

Considered is the drift of 10 icebergs and 18 ice fields in the northeastern part of the Barents Sea from late May to September 2009. The drift speed is estimated by GPS measurements of geographic coordinates, and the wind, using the air pressure field. The drift variability in the range of synoptic and intraseasonal variability is analyzed by the vector-algebraic method based on the model of the random Euclidean vector. The conjugacy of the drift with the wind is represented by the indices of vector regression (the theory of A.M. Obukhov) and vector correlation. Ice fields differ from icebergs by the high velocities of drift, significant variability, and higher correlation with the wind (0.85–0.99 for fields and 0.78–0.91 for icebergs). The wind and nonwind components of the drift are singled out by the Watanabe-Gudkovich correlation method. Wind coefficients and angles of deviation for the wind drift component amounted to 0.016–0.023 and −6°…+9° for fields and 0.010–0.015 and 10°–15° for icebergs. The cyclonic circulation is developed in the area of permanent surface currents (of the nonwind nature).