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Tkachenko K.S.,Samara State Academy of Social Sciences and Humanities
Russian Journal of Marine Biology | Year: 2014

The distribution and size-age structure of Acropora corals were studied in two Maldivian atolls that differ in their geographic position and sea surface temperature regimes. The frequency and strength of thermal anomalies for the last 2 decades had a significant influence on the abundance, mortality rates, and age structures of acroporid communities. The long-term temperature amplitude was higher and the maxima were more pronounced in the northernmost Ihavandippolu Atoll than those in the equatorial South Huvadhoo Atoll. These differences resulted in a 10.4% mean cover of Acropora at Ihavandippolu Atoll, whereas the Acropora cover in the South Huvadhoo Atoll reached 59.5%. In the northern atoll, the coral mortality rate after the 2010 thermal anomaly was 3 times higher than that in the southern atoll. Younger acroporid colonies (up to 2 years old) dominated the northern atoll reefs, while the southern atoll showed a high proportion of older mature colonies. In both atolls, healthy table colonies of Acropora cytherea with a disk diameter greater than 2 m were observed that apparently survived three thermal anomalies since 1998. The mechanisms of acclimatization of Acropora and the prospects for its dominance in the Maldives under changing environmental conditions are discussed. © 2014 Pleiades Publishing, Ltd.

Tkachenko K.S.,Samara State Academy of Social Sciences and Humanities
Russian Journal of Ecology | Year: 2015

The ecological status of coral communities in the island area of the Nha Trang Bay (Central Vietnam) has been evaluated in March to May 2013. The material has been sampled at five stations from depths of 3–6 m using the photoquadrat method. It has been shown that characteristics of these communities markedly change with distance from the Nha Trang City and the sources of eutrophication and sediment influx: the total coral cover and the proportion of acroporids increase from 5.3% to 82.6% and from 0 to 61% respectively, while the abundance of macroalgae decreases from 41.5% to 0; the species richness of corals also increases significantly, from 7 to 68 species per station. Possible causes of the long-term changes in the coral reef ecosystems of the Nha Trang Bay are discussed. © 2015, Pleiades Publishing, Ltd.

Zyn V.I.,Samara State Academy of Social Sciences and Humanities
Radiation Physics and Chemistry | Year: 2016

The electron impact polymerization of adsorbed vapors of a hydrocarbon vacuum oil with molecular mass 450 Da (C32H66) has been studied in-situ in the range 0-20 eV using ellipsometry and a servo system with the Kelvin's vibrating probe. This allowed registering at the same time the two energy-dependent characteristics (spectra) of the process: the film growth rate and the electrical potential of the irradiated surface. The first spectrum has two resonance maxima near 2.5 and 9.5 eV while the surface potential has only one weak extremum near 9.5 eV. The first growth rate peak at 2.5 eV was connected with a creation of radicals through a resonant process of the dissociative electron attachment and beginning polymerization. The peaks at 9.5 eV in both the spectra mean accelerating polymerization and decreasing surface charge owing to simultaneous birth of highly active radicals and free electrons. The single resonant process controlling both the processes simultaneously is the dissociative attachment of an electron to an anti-bonding molecular orbital, almost the same as at the 2.5 eV but differing by deeper decomposition of the transient anion, among the products of which are now not the radicals only but also free electrons. The kinetic curves obtained in pulsed regimes of the electron bombardment were qualitatively identical for different precursors and were used for calculations of cross sections of these processes. © 2016 Elsevier Ltd.

Allentoft M.E.,Copenhagen University | Sikora M.,Copenhagen University | Sjogren K.-G.,Gothenburg University | Rasmussen S.,Technical University of Denmark | And 66 more authors.
Nature | Year: 2015

The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought. © 2015 Macmillan Publishers Limited. All rights reserved.

Stavitsky S.A.,Tomsk Polytechnic University | Palukhin N.E.,Tomsk Polytechnic University | Kobenko J.V.,Tomsk Polytechnic University | Riabova E.S.,Samara State Academy of Social Sciences and Humanities
EPJ Web of Conferences | Year: 2016

Due to electric equipment development and complication it is necessary to have a precise and intense diagnosis. Nowadays there are two basic ways of diagnosis: analog signal processing and digital signal processing. The latter is more preferable. The basic ways of digital signal processing (Fourier transform and Fast Fourier transform) include one of the modern methods based on wavelet transform. This research is dedicated to analyzing characteristic features and advantages of wavelet transform. This article shows the ways of using wavelet analysis and the process of test signal converting. In order to carry out this analysis, computer software Mathcad was used and 2D wavelet spectrum for a complex function was created. © Owned by the authors, published by EDP Sciences, 2016.

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