Основные этапы сотрудничества КНР с арабскими странами Ближнего Востока в 1980-2010 гг.

The article describes the stages of China's cooperation with Arab countries of the Middle East in 1980-2010. The evolution of PRC's Middle Eastern strategy in the context of internal of domestic processes of political change is examined. The attention is paid on China's cooperation with the Arab states in the field of economics, education and mass media.В статье анализируются этапы развития отношений Китая с арабскими странами Ближнего Востока в период с 1980 по 2010 г. Автор исследует эволюцию ближневосточной стратегии КНР в контексте изменений внутриполитического курса развития страны, рассматривает взаимодействие Китая с арабскими государствами в сфере экономики, образования и СМИ

Extraction properties of new aminophosphinoxide compounds

Extraction of Sc(III) ions by new a-aminomethylphosphinoxides was studied. Preliminary experiments with acid solutions allowed for selection of low-basicity compounds, which demonstrated a poor coefficient of the acids extraction. When applied for the aqueous solution of various salts, they appeared to be good extractants of Sc(III), Fe(III), Bi(III), In(III), and lanthanide ions in toluene and chloroform and discriminated ?o(II), Ni(II), Cu(II), alkaline, and alkaline-earth elements. Copyright © Taylor & Francis Group, LLC

Механизм формирования пленок SnS химическим осаждением из водных растворов

The results of investigation of the growth mechanism of SnS thin films prepared by hydrochemical deposition by means of a scanning probe microscopy are presented. According to the results of a comparative analysis of layers morphology at different growth stages and the use of fractal formalism growth model of SnS films by clustercluster aggregation with elements of self-organization is proposed. It is shown that there is a solid layer, which again are deposited particles of the solution. The process has expressed periodic self-organizing nature. The study showed that the proposed model of film growth SnS when hydrochemical deposition agrees well with ex-periments and proves difficult coagulation mechanism of the formation of hard phase of the saturated aqueous solution.В работе представлены результаты исследования механизма роста пленок сульфида олова при химическом осаждении из водных растворов с использованием сканирующей зондовой микроскопии. По результатам сравнительного анализа морфологии слоев на различных этапах роста и использования фрактального формализма предложена модель роста пленок SnS путем кластер-кластерной агрегации с элементами самоорганизации

Liquid extraction of some rare earth elements with aminomethylphosphine oxides

Methods were developed of the solvent extraction from aqueous solutions of hydrochloric, nitric, and perchloric acids of the triply charged ions of rare earth elements including samarium, lutetium, dysprosium, neodymium, and ytterbium, using as reagents the lipophilic aminomethylphosphine oxides containing two or four dialkylphosphinyl groups, and toluene, chloroform, and methylene chloride as the organic media. The study of the effect of concentration of mineral acids on the degree of metal extraction showed that the highest extraction efficiency of lanthanides is achieved with bis(dihexylphosphinylmethyl)octylamine (I) from perchloric media: extraction degree 80%, whereas extraction from the solutions in two other acids did not exceed 30%. It was shown that the highest selectivity was reached at the extraction of scandium in all the extraction systems. A possible mechanism of extraction is discussed. © 2012 Pleiades Publishing, Ltd

Development and Prospects of National Intelligent System for Testing General Language Competencies Deployed Through Neural Network Solutions

The article presents the results of approbation of the intellectual system for testing general language competences (ISTOK) developed by testologists, linguists, specialists in methodology of teaching foreign languages and in artificial intelligence. This system includes a range of tests assessing language ability at levels from A2 to C1 of the Common European Framework of Reference (CEFR), as well as an adaptive placement test. All test materials are calibrated according to the CEFR. ISTOK is an adaptive testing system deployed through neural network solutions and providing assessment of receptive and productive language skills (reading, listening, speaking and writing) by using artificial intelligence and/or neurolinguistic models. The process of ISTOK development implied, apart from writing test items, putting together databases of writing and speaking assignments marked by professional assessors and assessment criteria for productive skills, as well as algorithms to identify various types of mistakes with the help of artificial intelligence. The results of various testing cohorts with the total number of test takers exceeding 5,000 demonstrated high reliability and objectified test validity. The new approach to language skills testing can be used for various purposes in higher education institutions, as well and to identify and/or confirm language proficiency of personnel in different organisations and businesses, while the principles of training and practical use of neurolinguistic models will find wide application in various fields of applied research

PECULIARITIES OF INTERACTION BETWEEN CITELLOPHILUS TESQUORUM ALTAICUS (IOFF, 1936) FLEA AND YERSINIA PESTIS WITH VARIOUS PLASMID COMPOSITION

Objective of the study is in vitro investigation of mutual relations between Citellophilus tesquorum altaicus and Yersinia pestis with various plasmid composition: influence of the strain on flea alimentary activity and mortality rate, frequency and dynamics of biofilm formation.Materials and methods. C. tesquorum altaicus were infected by three Yersinia pestis strains: virulent triple-plasmid I-3230 isolated in Mongolia, referential for the Tuva focus I-2638 carrying four plasmids (pYT, pYV, pYP, pTP 33) and also selected from it avirulent isogenic clone I-3480 that lost two plasmids (pYV, pYP). Peculiarities of interaction between fleas and Y. pestis strains were estimated through the lens of specimens with «conglomerates» and “blocks” for feeding, the period from infection prior to the beginning of conglomerates’ formation, alimentary activity, and mortality rate of the infected fleas.Results and conclusions. It was revealed that alimentary activity of the infected insects was higher than that of the control group, and the highest – in fleas infected with I-2638 strain. Greater numbers of dead fleas at feeding was noted in specimens inoculated with I-3230 strain. Predominant significance of I-2638 strain was established in C. tesquorum altaicus biofilm formation both as «conglomerates» and “blocks”. I-3480 strain also formed the conglomerates in fleas more actively than I-3230 lacking pTP33 plasmid. Thus, four-plasmid I-2638 strain surpassed triple-plasmid I-3230 and two-plasmid I-3480 strains in reference to all tested indicators except flea mortality rates. It may testify to co-adaptation of Y. pestis and C. tesquorum altaicus from the Tuva plague focus and to the possibility of a pTP33 functional role in enhancement of a biofilm formation in vivo

The Infestation of Fleas of the Long-Tailed Souslik with Entomoparasitic Nematodes in Tuva Mountain Natural Plague Focus

Entomoparasitic nematodes are supposed to be a link between parts of Yersinia pestis population in the environment and the flea vector. The aim of the study was to assess the prevalence and intensity of infestation in the fleas of the long-tailed souslik with entomoparasitic nematodes on the territory of Mongun-Taiginsky station in the Tuva natural plague focus. Materials and methods. Fleas were collected during the scheduled epizootiological surveys in 2019–2021. In the course of taxonomic identification the presence of parasitic nematodes was registered. In order to evaluate the intensity of nematode invasion, a total of 190 fleas were dissected. The number of adult parasitizing females and presence of larvae was recorded. Statistical processing of the data was performed with the help of conventional methods using the Excel software. The criterion χ2 was applied; the influence of various factors (species, gender of fleas) on the studied parameters was assessed through single- and two-factor analysis of variance. Results and discussion. During three years of observations, entomoparasitic nematodes were found in six species of fleas: Citellophilus tesquorum, Frontopsylla elatoides, Rhadinopsylla li transbaikalica, Frontopsylla hetera, Oropsylla alaskensis, and Neopsylla mana. The differences in infestation with nematodes between the species are presented. The highest invasion rate – 25.1–25.6 % – is observed in Rh. li transbaikalica. The gender of leas does not influence their infestation. It is established that invaded fleas are more often found in the nest than in the fur of animals, they are less actively migrate to the burrow entrance compared to not invaded ones. Evaluation of infestation prevalence has revealed that fleas Rh. li transbaikalica are the hosts for nematodes of mono- or oligoxenic species, which do not occur in other fleas

Building the Record of late Miocene to Pleistocene Explosive Activity in the Kurile-Kamchatka Volcanic Arc: Initial Results and Challenges

Large explosive eruptions are among the most extreme natural events and can produce hemispheric or even global catastrophic effects. One of the prerequisites of predicting future giant eruptions is the understanding of sizes and recurrence times of past similar events. Volcanism of the North Pacific arcs is highly explosive, which is attested by large nested calderas and numerous tephra layers in marine and terrestrial sediments..