All Articles

Summary: In the present work, we consider the metric questions of diffeomorphic mappings of the manifolds. We find such bases on tangential spaces of manifolds corresponding to given mappings, which allow investigate their metric properties, independent of connection coefficients, by using of strictly analysis’ methods. For simplicity of our considerations, we suffice with consideration of manifolds defined by finite number of maps. When our consideration is restricted with neighborhoods of some points, we shall suffice with one map defining the manifold.

Summary: It is considered the vector-valued grand Lebesgue space Lp) (X) ≡ Lp) (J;X), 1 < p < ∞, and the concept of a t-basis, generated by some bilinear map (where J = [−π, π)), is introduced. It is proved that the exponential system E ≡ eint n∈Z forms a t-basis for Np) (X), when X is a UMD space, where Np) (X) is the closure of Xvalued infinitely differentiable functions in Lp) (X). The concept of the t-Riesz property of the system E in Np) (X) is defined. It is established that this system has the t-Riesz property, when X is a UMD space. Using these facts, the X-valued grand Hardy classes mH± p) (X) of X-valued analytic functions are introduced, and some of their properties are proved. The obtained results are applied to establish the t-basicity of the perturbed exponential system in Np) (X).

Summary: In this work a nonlocal problem for the Laplace equation in an unbounded domain is considered. The notion of a strong solution of this problem is defined. Using the Fourier method, we prove the correct solvability of the considered problem in Sobolev spaces generated by a weighted mixed-norm. This problem in the classical formulation was previously considered by E. I. Moiseev [1]. The same type of problem was considered in the work of M. E. Lerner and O. A. Repin [2].

Summary: In this study, we examine cubic stochastic operators, which we will refer to as quasi-strictly non-Volterra cubic operators. Firstly, the definition of a quasi-strictly non-Volterra operator is provided, and the structure of an arbitrary quasi-strictly non- Volterra cubic operator on a two-dimensional simplex S2 is described. Secondly, the fixed and limit points of the quasi-strictly non-Volterra operator on S2 are investigated. It is proven that there exists a repelling unique fixed point.

Summary: This study investigates the impact of climatic factors on agricultural output between 1970 and 2022 in Türkiye. The Bayesian Model Averaging (BMA) method was utilized to select the independent variables for the model. The augmented ARDL (A-ARDL) approach was employed to analyze the cointegration relationship between the variables. Then, the CCR, DOLS, and FMOLS techniques were applied to assess the long-term dynamics. The key findings of the study are as follows: (i) The BMA analysis identified the carbon dioxide emissions, cultivated agricultural area, minimum average temperature, and 10 cm ground temperature as the significant independent variables. (ii) The A-ARDL results indicate a long-term association between the selected variables. (iii) The minimum average temperature is positively associated with the agricultural sector’s share in GDP. (iv) Increases in carbon dioxide emissions, 10 cm ground temperature, and cultivated agricultural area were found to decrease the agricultural sector’s share in GDP. In summary, the findings of study confirms the multi-dimensioned and non-linear character of climate-agriculture relations, challenging overly simplistic interpretations. From a policy perspective, the evidence puts emphasis on the need for climat-smart agricultural policies that bind together temperature regulation, emissions reduction, and efficient land use. Such insights are particularly significant for nations such as Türkiye that experience both extreme climatic volatility as well as structural challenges within their agricultural systems.

Summary: In our previously published articles, we presented for the first time the results of quantum mechanical calculations of the rеaction profile for a new rеaction involving N-substituted hydrazonеs with CCl4 in the presence of a catalytic complex based on CuCl and TMEDA, leading to the formation of halogenatеd vinyldiazеnyl systеms containing geminal chlorinе atoms at the terminal vinyl position. The DFT calculations of the elеctronic structure of the molеcules demonstrated that the introduction of electron-donating and electron-withdrawing substituents into the aromatic fragmеnts of the molеcules significantly affеcts their properties by altering elеctronic parameters and reactivity dеscriptors. Based on these findings and expеrimental data, it was of interest to perform calculations and analyze the energеtic profile of the reactions under conditions of qualitative changes in the substrate composition. The study showed that in the case of hydrazones with complеmentary elеctron density shifts (i.e., donor substituents in the aldеhyde moiety and acceptor substituents in the hydrazine moiety of the molecule), in addition to the еxpected formation of dichlorinated vinyldiazеnes (dichlorodiazadienes), nеw competitive reactions occur. The products of these reactions are pseudo-dimers (bis-hydrazone derivatives), formed by the coupling of two molеcules of the initial hydrazonе. Energеtic calculations were carried out for both reactions, viz the formation of dichlorovinyldiazenes and bis-hydrazone derivatives. Based on these studies, the mechanisms for the formation of bis-hydrazone derivatives were proposed for the first time.

Summary: The evolving macroeconomic landscape, shaped by the global financial crisis and the COVID-19 pandemic, poses significant challenges for economies worldwide. However, Central, Eastern, and Southeastern European (CESEE) countries have demonstrated resilience and rapid recovery during crises, driven by a surge in consumption fueled by domestic credit and robust export growth supported by flexible exchange rates and adaptive monetary policies. Prior to EU accession, substantial foreign direct investment (FDI) during privatization and restructuring facilitated knowledge and technology transfers in CESEE economies. This study examines the interplay of exports, real exchange rates, GDP growth, FDI, inflation, domestic credit, and the human development index (HDI) in the CESEE region from 1995 to 2022, covering the transition period, EU accession, and major crises. Employing a panel ARDL model, we account for asymmetric effects of these variables on exports. The results reveal that GDP, FDI, inflation, domestic credit, and HDI significantly and positively influence exports, with HDI and GDP exerting the strongest effects, underscoring the pivotal roles of human capital and economic growth in enhancing export competitiveness. Conversely, real exchange rate depreciation negatively impacts exports, though non-price factors, such as product quality, mitigate this effect. These findings provide a robust basis for targeted policy measures to strengthen economic resilience and export performance in the CESEE region.

Summary: Recently, our scientific group has been studying in detail the synthesis and structural properties of dichlorodiazadienes obtained from the interaction of N-substituted hydrazones of benzoyl and terephthalaldehyde with polyhalogen methanes in the presence of a CuCl catalyst. This class of compounds, in addition to their application as azo dyes, can be used as important synthons in the synthesis of other organic compounds. Various research works have been carried out in this area. Mainly, their reactions with nucleophiles have been widely studied. Taking all this into account, we have studied the solvolysis reactions of mono and bis dichlorodiazadienes and synthesized the corresponding compounds.Four novel compounds were synthesized and their antimicrobial activities were evaluated using agar well diffusion method. The results revealed that fungal strains were more sensitive to all compounds compared to bacteria. Pseudomonas aeruginosa was the most sensitive gram-negative bacterium to compound III (Methyl (Z)-2-(2-(4-chlorophenyl) hydrazineylidene)-2-phenylacetate) with 20.0 mm as the diameter of inhibition zone. Escherichia coli and Bacillus mesentericus were highly resistant to compounds I. Candida albicans was the most susceptible fungal strain to compound IV ((E)-1-(4-chlorophenyl)-2-(2,2-dichloro-1-phenylvinyl) diazene) with an inhibition zone of 24.0 mm.

Summary: We have been synthesized hydrogenated Schiff base ligand with Co(II), Cu (II) and Zn(II) complexes. Ligand was synthesized hydrogenation of salicylidene-aniline. Ligand and three metal complexes structure have been proved by spectral analyses. The antimicrobial properties of synthesized compounds have been investigated. Synthesized compounds have shown high antifungal and antibacterial properties. Comparing Schiff bases metal complexes with hydrogenated Schiff base complex compounds hydrogenated complex compounds has shown higher antimicrobial properties, because when azomethines group double bond break down and hydrogen atom enter the structure of ligand it changes complex formation ability of ligand and also influence antimicrobial properties. Other positive side of of our ligand and complex compounds, they have shown antimicrobial properties even 0,25% concentration and they are durable 6 month.

Summary: Fungicides are very important for agriculture, animal husbandry and medicine, as the various infections induced by certain fungi cause harm to plants and animals which are used as a source of food, as well as directly to humans themselves. More than 1,5 million deaths are caused by fungi each year, both the incidence of fungal infections and the resistance against already existing antifungal drugs are on the rise, which renders the search for inexpensive and new effective fungicides very urgent. On the other hand, some compounds containing 1,2,3-triazole moieties (for example, Radezolid and Cefatrizine) display strong antifungal activity and are used as fungicides. Azoles prevent lanosterol 14-alpha-demethylase enzyme from converting to ergosterol, and therefore inhibit growth of fungi. Today many scientists all across the world synthesize new compounds containing 1,2,3-triazole moieties and research their antifungal properties by applying them against various pathogenic fungal strains. This article is a review of recent scientific literature describing antifungal activity of compounds containing 1,2,3-triazole moieties.