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Number of results: 6
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Abstract

The sunflower stem weevil, Cylindrocopturus adspersus LeConte is a quarantine intra-stem pest of sunflower, distributed mainly in the United States, and discovered in the Kherson region of Ukraine in 2020. The objective of this study was to establish a possible distribution zone of this species in Ukraine based on the results of bioclimatic modeling. The model was built by using programs DIVA GIS version 7.5.0 and BIOCLIM, which search for areas that are suitable for a particular organism, through geographic information systems and by comparing the world climate with the climate of areas in which it has already been identified. Analysis of the model shows that in Ukraine the pest can acclimatize in the Kherson region only (zone with up to 2.5% probability). Geographically, the territory is limited to 46−47° of north latitude and to 33−34° of north longitude. It is located on the Black Sea Lowland and covers territory lying no higher than 50 meters above the Black Sea level, whose land- -surface temperature in July averages more than 28°С. The North Crimean Canal and Krasnoznaamyansky Canal pass through the territory, which is limited in the south by Sivash, Karkinitsky Bay and Dzharilgatsky Bay of the Black Sea, in the west − by the Dnipro Delta, and in the north − by Kakhovka Reservoir and Kakhovskiy canal. The analysis of values of climatic predictors for the territories which are suitable for acclimatization of a phytophage demonstrated its high ecological plasticity and potential ability to move not only on coastal territories, but also on territories with a continental climate.
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Authors and Affiliations

Sergey Moroz
1
Andrew Fokin
1

  1. Department of Integrated Protection and Plant Quarantine, National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
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Abstract

The relative relationships “yield – evapotranspiration” were used long time ago. The well known linear relationship yi = 1 – ky (1 – ei), where yi is relative yield, ky – yield response factor and ei – relative evapotranspiration was proposed. It’s usually assumed that ky is constant for a given crop and climatic conditions. It was found, however, that ky for late variety of maize H 708 varied through the study years (1984–1990) in the Plovdiv region (South Bulgaria, altitude 150 m). During the dry years it was significantly higher than in the medium and humid years. The range of ky for maize in this location was 1.12–1.90, the average value being 1.50. The climate in the Sofia region (the ex-perimental field of Chelopechene, altitude 550 m) is comparatively more humid. The two regions approximately outlined the boundaries of the appropriate economical conditions for grain maize pro-duction. The experiments in the Sofia region were carried out in the years 1994–2000. The seven years results for mean variety maize showed that the relationships “yield – evapotranspiration” and, respectively, ky varied at these climatic conditions too. The highest ky value was 1.41 for the driest year (2000) and the lowest value – 1.05 for the most wet years (1995, 1999). The value of ky for av-erage years was 1.21. The yield response factor ky is of more significance when the relative evapotranspiration is less than 0.7–0.8. Thus, the extreme or the average values of ky could be used for the corresponding climatic regions. The relationships between ky and relative yield were estab-lished without considering irrigation.

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Authors and Affiliations

Bojidara Mladenova
Ivan Varlev
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Abstract

A new model of ideal signal sampling operation is developed in this paper. This model does not use the Dirac comb in an analytical description of sampled signals in the continuous time domain. Instead, it utilizes functions of a continuous time variable, which are introduced in this paper: a basic Kronecker time function and a Kronecker comb (that exploits the first of them). But, a basic principle behind this model remains the same; that is it is also a multiplier which multiplies a signal of a continuous time by a comb. Using a concept of a signal object (or utilizing equivalent arguments) presented elsewhere, it has been possible to find a correct expression describing the spectrum of a sampled signal so modelled. Moreover, the analysis of this expression showed that aliases and folding effects cannot occur in the sampled signal spectrum, provided that the signal sampling is performed ideally.
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Authors and Affiliations

Andrzej Borys
1
ORCID: ORCID

  1. Department of Marine Telecommunications, Faculty of Electrical Engineering, Gdynia Maritime University, Gdynia, Poland
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Abstract

In this interview conducted at the XXIII International Congress of Historical Sciences in Po-znan, Q. Edward Wang (Professor of History at Rowan University in the US and Changjiang Professor of History at Beijing University in China) addresses the main problems in global and comparative historiography. Elaborating upon the background and impact of his scientific con-tributions, Prof. Wang discusses the modernization of Chinese historical writing, the challenges of comparative historiography, the status of historical studies today, and the future of historical theory. In addition, he refers to his recent studies in culinary history as instances of a new model of global historiography.
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Authors and Affiliations

Dawid Rogacz
1
ORCID: ORCID

  1. Uniwersytet im. Adama Mickiewicza w Poznaniu
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Abstract

The letter of Muscovy ruler Boris Godunov which is held in the Library of Kórnik, is the earliest historical document that testifies about the relations between the government of Muscovy and Ukrainian Cossacks since the end of the sixteenth century. In the article are reviewed the historical context of such contacts and their long term consequences. At that time, led by Krzysztof Kosynskyi, Cossacks entered into conflict with powers of Commonwealth. Godunov informed Cossacks that his government invites them for military service. It was the first time when Cossacks obtained the opportunity to make a choice between the service to the Polish King or Muscovy Tzar. During the next a half of the century, Ukrainian Cossacks transformed into a powerful military corporation, which influenced on the balance of powers in international relations of the region. Later on, when in the consequence of the war with Poland, Cossacks switched themselves to the side of Muscovy in 1654, this change provided a foundation for the hegemony of Muscovy in East Europe.

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Authors and Affiliations

Serhiy Lepyavko

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