On the patterns of trade convergence in European transition countries

In current study we analyze the convergence of trade between Central and Eastern European countries (CEECs) and European Union (EU) during the period from 1984 to 2004. In our extension of the theoretical framework of Helpman, Melitz and Rubinstein (2005) with heterogeneous firms we discuss the influence of economic fundamentals and trade cost on extensive and intensive margins of trade. Then, we use gravity model of trade to calculate potentials for CEECs trade with EU-15 countries. As a result, we develop convergence measures for CEECs exports and imports trade flows with EU-15. Moreover, we provide decomposition of trade flows on extensive and intensive margins, and construct convergence measures for each of the trade components. Finally, we analyze the mechanics of trade convergence process in selected CEECs. Current paper contributes to better understanding of trade convergence patterns in European transition countries, providing policy-makers in transition economies with useful insights on the role of different trade components in the convergence process.trade convergence, gravity model, extensive and intensive margins, Hummels-Klenow decomposition

Genotypic, physiological and biochemical features of Desulfovibrio strains in a sulfidogenic microbial community isolated from the soil of ferrosphere

The purpose of this work was the isolation of the predominant representatives of sulfate-reducing bacteria (SRB) of the sulfidogenic microbial community separated from the soil ferrosphere and the examination of their morphological, physiological, biochemical and genotypic peculiarities, the evaluation of some physiological processes under co-culturing with their satellite species Anaerotignum propionicum. During the study two isolates of sulfatereducing bacteria NUChC SRB1 and NUChC SRB2 were obtained from sulfidogenic microbial community isolated from soil ferrosphere on Postgate’s “B” medium and their belonging to different strains (using ISSR-PCR method) was proved. As a result of molecular-genetic analysis of the strains, a 16S rRNA gene fragments of 613 bp and 522 bp were amplified and sequenced. The strains were identified as Desulfovibrio oryzae by the complex of microbiological, physiological and biochemical features and on the basis of 16S rRNA gene sequences (phylogenetic analysis). The 16S rRNA gene sequences were submitted in GenBank as MT102713 (NUChC SRB1) and MT102714 (NUChC SRB2). The co-cultivation of isolated SRB strains with A. propionicum NUChC Sat1 strain (in the absence of electron donors, the presence of sulfates and yeast extract) showed the formation of sulfur-reducing bacteria of hydrogen sulfide, which was not observed during their mono-cultivation. In this case, the phenomenon of syntrophy probably takes place- co-growth on the nutrient substrate, and the electron donor appears due to the use of the yeast extract compounds by the NUChC Sat1 strain. Therefore, in the sulfidogenic community isolated from the soil ferrosphere, there is a mutual growth of the association of bacteria D. oryzae and A. propionicum, which is caused by trophic interaction. Possibly the contribution of these associated bacteria to the corrosion process lies in the utilization of hydrogen (D. oryzae) and the formation of substrate products of SRB metabolism (hydrogen and organic acids), which are both corrosive compounds (A. propionicum). Without a doubt the corrosion process involving this association needs further investigation

Ecological suitability peas (Pisum sativum) varieties to climate change in Ukraine

Saabunud / Received 19.05.2021 ; Aktsepteeritud / Accepted 29.09.2021 ; Avaldatud veebis / Published online 29.09.2021 ; Vastutav autor / Corresponding author: Ihor Kupchuk [email protected] varieties of peas can realize about 50% of their productive potential. One of the main reasons for this is the wrong choice of variety for specific ecological growing conditions. Therefore, the purpose and task of our research are to analyze the current range of peas, included in the State Register of plant varieties suitable for cultivation in Ukraine in terms of their real productivity and resistance to drought and disease in the context of climate change in the direction of drought and temperature rise. Assessment of agroecological stability of pea varieties was carried out by elaboration of the State Register of Plant Varieties Suitable for Distribution in Ukraine for 2020, 2010 and Official Descriptions of Plant Varieties and Suitability Indicators submitted in the official bulletins "Protection of Plant Variety Rights" published in Information and reference system "Variety". The most resistant to disease in Ukraine are varieties of peas 'Verbal', 'Prystan', 'Есо', 'Atanas', 'Haiduk'. Varieties are marked by the highest drought resistance 'Verbal', 'Album', 'Alssas', 'Kampus'. The most productive varieties were peas 'Kosmai', 'Album', 'Haiduk', 'Trendy'. The increase in the average annual air temperature in Ukraine during 2001–2020 by 19.3% (8.2–9.9 °C) led to a decrease in the yield of peas by 13.7%, but an increase in the score of resistance of pea varieties to diseases by 25.0%, the score of drought resistance – by 18.8%. Comparison of indicators of disease resistance, drought resistance and productivity of pea varieties for 2020 and 2010 showed that the score of resistance of pea varieties sown to diseases in the period from 2010 to 2020 increased from 6.3 to 8.4 points, i.e. by 25.0%. Drought resistance of pea varieties in 2020 compared to 2010 increased from 6.5 to 8.0 points, which is 18.8%. At the same time, the grain productivity of pea varieties in 2020 compared to 2010 decreased from 3.57 t ha–1 to 3.08 t ha–1, which is 13.7%

On the patterns of trade convergence in European transition countries

In current study we analyze the convergence of trade between Central and Eastern European countries (CEECs) and European Union (EU) during the period from 1984 to 2004. In our extension of the theoretical framework of Helpman, Melitz and Rubinstein (2005) with heterogeneous firms we discuss the influence of economic fundamentals and trade cost on extensive and intensive margins of trade. Then, we use gravity model of trade to calculate potentials for CEECs trade with EU-15 countries. As a result, we develop convergence measures for CEECs exports and imports trade flows with EU-15. Moreover, we provide decomposition of trade flows on extensive and intensive margins, and construct convergence measures for each of the trade components. Finally, we analyze the mechanics of trade convergence process in selected CEECs. Current paper contributes to better understanding of trade convergence patterns in European transition countries, providing policy-makers in transition economies with useful insights on the role of different trade components in the convergence process

On the patterns of trade convergence in European transition countries

In current study we analyze the convergence of trade between Central and Eastern European countries (CEECs) and European Union (EU) during the period from 1984 to 2004. In our extension of the theoretical framework of Helpman, Melitz and Rubinstein (2005) with heterogeneous firms we discuss the influence of economic fundamentals and trade cost on extensive and intensive margins of trade. Then, we use gravity model of trade to calculate potentials for CEECs trade with EU-15 countries. As a result, we develop convergence measures for CEECs exports and imports trade flows with EU-15. Moreover, we provide decomposition of trade flows on extensive and intensive margins, and construct convergence measures for each of the trade components. Finally, we analyze the mechanics of trade convergence process in selected CEECs. Current paper contributes to better understanding of trade convergence patterns in European transition countries, providing policy-makers in transition economies with useful insights on the role of different trade components in the convergence process

Microbiological and genetic characteristics of Bacillus velezensis bacillibactinproducing strains and their effect on the sulfate-reducing bacteria biofilms on the poly(ethylene terephthalate) surface

. It was evaluated the antibiofilm-forming properties of NUChC C1 and NUChC C2b isolates (from the collection of the Department of Biology of the T.H. National University “Chernihiv Colehium”) against the sulfate-reducing bacteria biofilms on the poly(ethylene terephthalate) surface. NUChC C1 and NUChC C2b isolates were isolated by classical microbiology methods on Postgate’s “B” medium and their cultural-morphological, some physiological-biochemical properties and molecular-genetic characteristics were investigated. To identify bacteria the sequencing and analysis of the 16S rRNA gene were carried out. The bacteria were identified as Bacillus velezensis. Based on PCR-ISSR analysis, it was found that the studied bacteria belong to different strains. The 16S rRNA gene sequences were submitted in GenBank as MN508954.1 (NUChC C1), MN749356.1 and MN749357.1 (NUChC C2b). In the genome of B. velezensis the presence and transcriptional activity of the genes for the synthesis of bacillibactin (dhbC, dhbF), fengycin (fenA) and polyglutamic acid (epsK) were studied. Among these only genes belonging to bacillibactin synthesis operon were detected and only they demonstrated activity. The observed mode of dhbC and dhbF genes expression during 144 hours of cultivation differed between two B. velezensis strains: gradually increasing in NUChC C1 and sharply increased after 24 hours with decreasing on 144th hour in NUChC C2b. Antagonistic properties of the studied strains of B. velezensis against sulfate-reducing bacteria Desulfovibrio oryzae NUChC SRB1 and NUChC SRB2 were not observed. Siderophore-producing strains of Bacillus velezensis inhibit the formation of bacterial biofilms on the polymeric material poly(ethylene terephthalate) during its long-term exposure (50 days) in a culture of sulfatereducing bacteria under conditions of sufficient iron supply. Bacillibactin-producing strains prevent the development of bacterial biofilms on the poly(ethylene terephthalate) surface. This is one of the reasons for the prolongation of the process of poly(ethylene terephthalate) biodegradation in natural ecosystems

Methodical approaches to calculation of cost of educating specialists in institutes of higher education in Ukraine

У статті розглянуто сучасні підходи до визначення вартості підготовки одного студента вищого навчального закладу ІІІ – ІV рівнів акредитації. Запропоновано авторську методику оцінки середньої орієнтовної вартості підготовки одного фахівця, яка враховує основні складові витрат ВНЗ. Запровадження нормативу вартості підготовки фахівців дозволить підвищити ефективність процесу формування та розміщення державного замовлення на підготовку кадрів на конкурсних засадах. The article considers modern approaches to calculation of cost of educating one student of an institute of higher education of the third and fourth levels of accreditation. It proposes author’s own system of assessment of an average approximate cost of educating one specialist, which includes basic components of costs of institutes of higher education. Introduction of a standard of cost of educating specialists would allow increase of effectiveness of the process of formation and allocation of the state order for staff training on a competitive basis

THE THEORY AND PRACTICE OF HIGHER EDUCATIONAL INSTITUTIONS MANAGEMENT IN UKRAINE

The theory and practice of management of higher educational establishments of Ukraine has a long history and is characterized by considerable experience and traditions. The article presents the findings study of the theory and practice of management in higher educational institutions in Ukraine in XIX – beginning of XXI century. The main periods of development of the theory and practice of management in higher educational institutions in Ukraine in XIX – beginning of XXI century is determined: 1802–1832, 1833–1862, 1863–1883, 1884–1917, 1917–1920, 1921-1990, 1991–2019 years as well as the characteristic features and tendencies of each of them. Views of N. Pirogov (the complete autonomy, the decentralization of universities’ management, the Ministerial panel of respected scientists interuniversity publicity etc.), K. Ushinskiy (the internal university management, the management of schools district etc.), M. Kostomarov (the idea of «an open university», increasing the authority of the University and others) and others are actualized in the investigation. The works above authors as a reliable on the basis in the development of the new trend of interdisciplinary scientific knowledge – universitology.

Дослідження впливу багатокомпонентного навантаження на тонкостінні конструкції з болтовими з’єднаннями

Features of influence of various factors on the stress-strain state of composite thin-walled structures with bolted connection of separate elements were studied on an example of the test problem. As an example of such structures, a metallic granary (a silo) consisting of panels connected with bolts was taken. The test structure contained two lapping narrow flat strips. A bolt is inserted in bolt holes bored in these strips and pre-tightened. Friction and slipping of the strips and the bolt, contact between the side surface of the bolt and the holes as well as mutual influence of bending and stretching were taken into consideration. Thus, the model has taken into consideration geometric, physical and structural nonlinearities. The system was subjected to a transverse load applied to one side of the strip. Staged loading of the systems was modeled. It was established that under load, the studied system acquires a deflection which unevenly increases with the load increase. This is determined by the fact that it is affected by both elastic deformation of the strips and mutual slip in the connection zone. When the gap between the bolt and the holes in the panels finally vanishes, mainly elastic deformation of the system takes place. Residual deflection was established in the system after the first unloading. It was also established that longitudinal forces act in the system. They can be much larger than transverse forces from the load. The system featured strong mutual influence of bending and stretching of the strip. As a result of the studies, factors determining stress-strain state of the studied system were determined: geometric nonlinearity, contact interaction, friction and slip, connection between deflection and stretching. Thus, the design model for such thin-walled structures will be inadequate without all these factors, the results of calculations with its application will have significant errors and recommendations will be unreliable. The conducted studies have made it possible to develop more adequate models for analysis of reaction of composite thin-walled structures to the effect of loadingНа примере тестовой задачи исследуются особенности влияния различных факторов на напряженно-деформированное состояние составных тонкостенных конструкций с болтовым соединением отдельных элементов. Примером таких конструкций являються металлические зернохранилища – силосы, состоящие из панелей, которые соединяются болтами. Тестовая конструкция содержит две узких плоских полосы, соединенных внахлест. В отверстия в этих полосах размещен болт с предварительной затяжкой. Учитывается трение и проскальзывание полос и болта, контакт боковой поверхности болта и отверстий, а также взаимное влияние изгиба и растяжения. Таким образом, в модели учтены геометрическая, физическая и структурная нелинейности. Система подвергается воздействию поперечной нагрузки, которая приложена к одной стороне полосы. Моделируется поэтапная нагрузка систем. Установлено, что при нагрузке исследуемая система приобретает прогиб, который неравномерно возрастает с ростом нагрузки. Это обусловлено тем, что на него влияет и упругая деформация полос, и взаимное проскальзывание в зоне соединения. При окончательной выборке зазора между болтом и отверстиями в панелях происходит преимущественно упругое деформирование системы. После первой разгрузки в системе устанавливается остаточный прогиб. Также установлено, что в системе действуют продольные усилия, которые могут быть намного больше поперечных сил от нагрузки. Характерно сильное взаимное влияние изгиба и растяжения полосы. В результате исследований установлены факторы, определяющие напряженно-деформированное состояние исследованной системы: геометрическая нелинейность, контактное взаимодействие, трение и проскальзывание, связанность изгиба и растяжения. Таким образом, без учета всех этих факторов расчетная модель для подобных тонкостенных конструкций будет неадекватной, результаты расчетов с ее применением – иметь значительные погрешности, а рекомендации – недостоверны. Осуществленные исследования дают возможность разработки более адекватных моделей для анализа реакции составных тонкостенных конструкций на действие нагрузкиНа прикладі тестової задачі досліджуються особливості впливу різних чинників на напружено-деформований стан складених тонкостінних конструкцій із болтовим з’єднанням окремих елементів. Прикладом таких конструкцій є металічні зерносховища – силоси, які складаються із панелей, що з’єднуються болтами. Тестова конструкція містить дві вузьких плоских смуги, з’єднаних внакид. У отвори в цих смугах розміщений болт із попереднім затягуванням. Ураховується тертя і проковзування смуг і болта, контакт бічної поверхні болта і отворів, а також взаємний вплив вигину і розтягування. Таким чином, у моделі враховані геометрична, фізична і структурна нелінійності. Система піддається дії поперечного навантаження, яке прикладене до однієї сторони смуги. Моделюється поетапне навантаження систем. Встановлено, що при навантаженні досліджувана система набуває прогин, який нерівномірно зростає з ростом навантаження. Це зумовлено тим, що на нього впливає і пружна деформація смуг, і взаємне проковзування в зоні з’єднання. При остаточному вибиранні зазору між болтом і отворами в панелях відбувається переважно пружне деформування системи. Після першого розвантаження в системі установлюється залишковий прогин. Також встановлено, що у системі діють поздовжні зусилля, які можуть бути набагато більшими від поперечних сил від навантаження. Характерним є сильний взаємний вплив вигину і розтягування смуги. У результаті досліджень встановлено чинники, що визначають напружено-деформований стан дослідженої системи: геометрична нелінійність, контактна взаємодія, тертя і проковзування, зв’язаність вигину і розтягування. Таким чином, без урахування всіх цих чинників розрахункова модель для подібних тонкостінних конструкцій буде неадекватною, результати розрахунків із її застосуванням матимуть значні похибки, а рекомендації – недостовірними. Здійснені дослідження дають можливість розроблення більш адекватних моделей для аналізу реакції складених тонкостінних конструкцій на дію навантаженн