Fabrication of the Ni[3]Al-based alloy formed by spark plasma sintering of VKNA powders

The material based on Ni[3]Al intermetallic has been obtained from the industrial powder of a VKNA type by the method of spark plasma sintering. Materials sintering was conducted at the temperature of 1100 °С, compacting pressure of 20 MPa, and during soaking time equal to 5 minutes. The heating rate of samples amounted to 50 and 200 °С/min. It has been established that the material obtained by sintering at the rate of 50 °С/min possesses a maximum value of density (5.93 g/cm{3}) and a maximum level of bending strength (~ 400 MPa)

Fabrication of the Ni[3]Al-based alloy formed by spark plasma sintering of VKNA powders

The material based on Ni[3]Al intermetallic has been obtained from the industrial powder of a VKNA type by the method of spark plasma sintering. Materials sintering was conducted at the temperature of 1100 °С, compacting pressure of 20 MPa, and during soaking time equal to 5 minutes. The heating rate of samples amounted to 50 and 200 °С/min. It has been established that the material obtained by sintering at the rate of 50 °С/min possesses a maximum value of density (5.93 g/cm{3}) and a maximum level of bending strength (~ 400 MPa)

Antioxidative Activity of Ferrocenes Bearing 2,6-Di-Tert-Butylphenol Moieties

The antioxidative activity of ferrocenes bearing either 2,6-di-tert-butylphenol or phenyl groups has been compared using DPPH (1,1-diphenyl-2-picrylhydrazyl) test and in the study of the in vitro impact on lipid peroxidation in rat brain homogenate and on some characteristics of rat liver mitochondria. The results of DPPH test at 20°C show that the activity depends strongly upon the presence of phenolic group but is improved by the influence of ferrocenyl fragment. The activity of N-(3,5-di-tert-butyl-4-hydroxyphenyl)iminomethylferrocene (1), for instance, was 88.4%, which was higher than the activity of a known antioxidant 2,6-di-tert-butyl-4-methylphenol (BHT) (48.5%), whereas the activity of N-phenyl-iminomethylferrocene 2 was almost negligible −2.9%. The data obtained demonstrate that the compounds with 2,6-di-tert-butylphenol moiety are significantly more active than the corresponding phenyl analogues in the in vitro study of lipid peroxidation in rat brain homogenate. Ferrocene 1 performs a promising behavior as an antioxidant and inhibits the calcium-dependent swelling of mitochondria. These results allow us to propose the potential cytoprotective (neuroprotective) effect of ditopic compounds containing antioxidant 2,6-di-tert-butylphenol group and redox active ferrocene fragment

Genetic and morphologic determination of diatom community composition in surface sediments from glacial and thermokarst lakes in the Siberian Arctic

Lakes cover large parts of the climatically sensitive Arctic landscape and respond rapidly to environmental change. Arctic lakes have different origins and include the predominant thermokarst lakes, which are small, young and highly dynamic, as well as large, old and stable glacial lakes. Freshwater diatoms dominate the primary producer community in these lakes and can be used to detect biotic responses to climate and environmental change. We used specific diatom metabarcoding on sedimentary DNA, combined with next-generation sequencing and diatom morphology, to assess diatom diversity in five glacial and 15 thermokarst lakes within the easternmost expanse of the Siberian treeline ecotone in Chukotka, Russia. We obtained 163 verified diatom sequence types and identified 176 diatom species morphologically. Although there were large differences in taxonomic assignment using the two approaches, they showed similar high abundances and diversity of Fragilariceae and Aulacoseiraceae. In particular, the genetic approach detected hidden within-lake variations of fragilarioids in glacial lakes and dominance of centric Aulacoseira species, whereas Lindavia ocellata was predominant using morphology. In thermokarst lakes, sequence types and valve counts also detected high diversity of Fragilariaceae, which followed the vegetation gradient along the treeline. Ordination analyses of the genetic data from glacial and thermokarst lakes suggest that concentrations of sulfate, an indicator of the activity of sulfate-reducing microbes under anoxic conditions, and bicarbonate, which relates to surrounding vegetation, have a significant influence on diatom community composition. For thermokarst lakes, we also identified lake depth as an important variable, but sulfate best explains diatom diversity derived from genetic data, whereas bicarbonate best explains the data from valve counts. Higher diatom diversity was detected in glacial lakes, most likely related to greater lake age and different edaphic settings, which gave rise to diversification and endemism. In contrast, small, dynamic thermokarst lakes are inhabited by stress-tolerant fragilarioids and are related to different vegetation types along the treeline ecotone. Our study demonstrated that genetic investigations of lake sediments can be used to interpret climate and environmental responses of diatoms. It also showed how lake type affects diatom diversity, and that such genetic analyses can be used to track diatom community changes under ongoing warming in the Arctic

Digital receivers for low-frequency radio telescopes UTR-2, URAN, GURT

This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the UTR-2 radio telescope, the URAN VLBI system, and the GURT new generation radio telescope. Here we detail these receivers developed for operation in the strong interference environment that prevails in the decameter wavelength range. Data collected with these receivers allowed us to discover numerous radio astronomical objects and phenomena at low frequencies, a summary of which is also presented.Comment: 24 pages, 15 figure

Russia’s Eurasian past, present and future: rival international societies and Moscow’s place in the post-cold war world

The failure of post-Soviet Russia to integrate into the West became evident with the 2014 Ukraine crisis, leading Moscow to accelerate its declared “pivot to the East”. However, the increased dependence on China carries its own risks, such as the danger of becoming Beijing’s junior partner. For an erstwhile superpower that continues to declare and prize its autonomy in international affairs, this is a particularly unappealing prospect. Thus, it remains to be seen whether a genuinely balanced partnership can exist between both countries. This article uses insights from Adam Watson’s pendulum theory to explore Russia’s post-2014 Eurasian predicament. We argue that the rapid rightward swing of the pendulum in the Euro-Atlantic order following the end of the Cold War has proven indigestible for Moscow. The article then moves to discuss the Sino-Russian relationship in the context of the emerging Eurasian space. It concludes that the growing disillusionment of Russian leaders with the West since the 2000s, along with the normative convergence between Moscow and Beijing, has led to a closer partnership between the two. Yet the partnership is also riddled with a number of insecurities on Moscow’s side that could undermine the long-term prospects for cooperation between Russia and China

Elite opinion and foreign policy in post-communist Russia

Russian elite opinion on matters of foreign policy may be classified as ‘Liberal Westerniser’, ‘Pragmatic Nationalist’ and ‘Fundamentalist Nationalist’, terms that reflect longstanding debates about the country’s relationship with the outside world. An analysis of press statements and election manifestoes together with a programme of elite interviews between 2004 and 2006 suggests a clustering of opinion on a series of strategic issues. Liberal Westernisers seek the closest possible relationship with Europe, and favour eventual membership of the EU and NATO. Pragmatic Nationalists are more inclined to favour practical co-operation, and do not assume an identity of values or interests with the Western countries. Fundamentalist Nationalists place more emphasis on the other former Soviet republics, and on Asia as much as Europe, and see the West as a threat to Russian values as well as to its state interests. Each of these positions, in turn, draws on an identifiable set of domestic constituencies: Liberal Westernisers on the promarket political parties, Pragmatic Nationalists on the presidential administration and defence and security ministries, and Fundamentalist Nationalists on the Orthodox Church and Communists

Epizootic pertussis focus of hamadryad baboons

The absence of an adequate experimental animal model makes difficult study of immunity against whooping cough and its pathogenesis. Experimental whooping cough reported by us earlier in pubescent non-human primates of the Old World was accompanied by specific clinical and laboratory marks in the absence of cough. The possibility of pertussis modelling while experimental whooping cough in impuberal hamadryad baboons was investigated. In the process of selection of monkeys for the further studies for perfecting of experimental model for pertussis research unexpectedly were detected specific pertussis antibodies in impuberal hamadryad baboons.The aim of the study: revealing of source of infection and transmission of pertussis to hamadryad baboons and investigation of response of antibody-positive impuberal hamadryad baboons to secondary contagion by B. pertussis bacteria while experimental infection.Results. 18 veterinary checked, somatically healthy hamadryad baboons of various gender managed in two neighboring cages. Specific pertussis IgM and IgG antibodies were found in blood serum of all the animals and one of the monkey keepers. By real-time PCR in nasopharyngeal swabs of the monkey keeper and three 7- and 9-month-old hamadryad baboons were registered single B. pertussis genom equivalents. Seropositive impuberal hamadryad baboons were experimentally challenged by virulent B. pertussis 475 strain. Quantity of B. pertussis genom equivalents and percentage of IgM and IgG antibodies in impuberal hamadryad baboons after experimental infection were detected. These results were comparable with such received after secondary experimental challenge of monkeys by B. pertussis. Humoral immuneresponse was characterized by booster effect and rapid B. pertussis elimination.Conclusion. The case of transmission of B.pertussis bacteria to hamadryad baboons by natural contagion and epizootic focus of pertussis in apery conditions were registered. In dynamics of immune response and level of bacterial load in experimentally infected impuberal and pubescent hamadryad baboons were not revealed significant differences. The possibility of asymptomatic B.pertussis transmission from man to monkey and from monkey to man without definitive spasmodic cough was reviewed. Pertussis research perspectives using experimental model of non-human primates of the Old World were marked

Паразиты дальневосточного леопарда (Panthera pardus orientalis) на юго-западе Приморского края России

The results of long-term studies of invasions of the Panthera pardus orientalis, Schlegel 1857. The study of parasitic invasions of the Far Eastern leopard was carried out by two methods. The first method included the study of excrement of the Far Eastern leopard collected in different seasons of the year from January 2009 to December 2014 by the Kotelnikov-Khrenov method. The second method is a complete parasitologic autopsy on Scriabin, the dead animals on the basis of PGHS. The autopsy was conducted by the chief veterinarian of the Primorsky Krai, and the autopsy report was compiled. To analyze the data obtained, the indicator was used - the index of occurrence, expressed as a percentage. As a result, the species composition of helminths parasitizing the Far Eastern leopard is supplemented by species of nematodes - Ancylostoma sp., Gnathostoma spinigerum Capillaria sp., Dirofilaria sp; cestodes - Taenia sp., Dipylidium caninum, Spirometra erinaceieuropei, Mesocestoides lineatus; trematodes - Nanophyetus salmicola schikhobalowi, Clonorchis sinensis, Metagonimus yokogawa. Dominiruet monoinvasion (66,6%). Di-invasion and triinvasia are much less common - 17,7% and 4,4%. Of the protozoans, oocysts were found isospora rivolta. On the body of the dead animals were found ixodid mites - Haemaphysalis flava, Haemaphysalis longicornis, Haemaphysalis japonica douglasi, Haemaphysalis punctate. It indicates the presence in the excrement of fleas of genus Ctenocephala и клещей рода and mites of the genus Otodectes.Цель исследования - выявить экто- и эндопаразитов дальневосточного леопарда (Panthera pardus orientalis, Schlegel 1857). Материалы и методы. Изучение паразитарных инвазий дальневосточного леопарда проводили двумя методами. Первый метод включал исследование фекалий дальневосточного леопарда, собранных в разные сезоны года с января 2009 г. по декабрь 2014 г. методом Котельникова-Хренова. Второй метод включал полное гельминтологическое вскрытие по Скрябину погибших животных на базе Приморской государственной сельскохозяйственной академии. Вскрытие проводили главным ветеринарным врачом Приморского края; составлен протокол вскрытия. Собранных паразитов фиксировали и обрабатывали стандартными методиками. Определение вида клещей проводили по определителю Н. A. Филипповой (1997). Для анализа полученных данных использовали показатель - индекс встречаемости, выраженный в процентах. Результаты и обсуждение. Видовой состав гельминтов, паразитирующих у дальневосточного леопарда, дополнен видами нематод - Ancylostoma sp., Gnathostoma spinigerum, Capillaria sp., Dirofilaria sp; цестод - Taenia sp., Dipylidium caninum, Spirometra erinaceieuropei, Mesocestoides lineatus; трематод - Nanophyetus salmicola schikhobalowi, Clonorchis sinensis, Metagonimus yokogawa. Доминирует моноинвазия (66,6 %). Дииинвазия и триинвазия наблюдаются гораздо реже - 17,7 и 4,4 % соответственно. Из простейших были обнаружены ооцисты Isospora rivolta. На теле погибших животных были найдены иксодовые клещи Haemaphysalis flava, H. longicornis, H. japonica douglasi, H. punctate. Указывается на нахождение в фекалиях блох рода Ctenocephala и клещей рода Оtodectes