Publications by authors named "Vladimir Krapivin"

In this work a new donor of nitric oxide (NO) with antibacterial properties, namely nitrosyl iron complex of [Fe(CHC-SNH)(NO)][Fe(CHC-SNH)(SO)(NO)] composition (complex ), has been synthesized and studied. Complex was produced by the reduction of the aqueous solution of [Fe(SO)(NO)] dianion by the thiosulfate, with the further treatment of the mixture by the acidified alcohol solution of thiobenzamide. Based on the structural study of (X-ray analysis, quantum chemical calculations by NBO and QTAIM methods in the frame of DFT), the data were obtained on the presence of the NO…NO interactions, which stabilize the DNIC dimer in the solid phase.

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The best way to study digenean diversity combines molecular genetic methods, life-cycle studies and elaborate morphological descriptions. This approach has been barely used for one of the most widespread digenean taxa parasitizing fish – the superfamily Hemiuroidea. Here, we applied the integrative approach to the hemiuroideans from the family Derogenidae parasitizing fish at the White and Barents Seas.

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The year 2020 ended with a significant COVID-19 pandemic, which traumatized almost many countries where the lockdowns were restored, and numerous emotional social protests erupted. According to the World Health Organization, the global epidemiological situation in the first months of 2021 deteriorated. In this paper, the decision-making supporting system (DMSS) is proposed to be an epidemiological prediction tool.

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Truncated life cycles may emerge in digeneans if the second intermediate host is eliminated, and the first intermediate host, the mollusc, takes up its role. To understand the causes of this type of life cycle truncation, we analyzed closely related species of the genus (Acanthocolpidae) with three-host and two-host life cycles. The life cycle of involves two hosts: wolffishes of the genus as the definitive host and the common whelk as the intermediate host.

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The aim of this paper is to develop an information-modeling method for assessing and predicting the consequences of the COVID-19 pandemic. To this end, a detailed analysis of official statistical information provided by global and national organizations is carried out. The developed method is based on the algorithm of multi-channel big data processing considering the demographic and socio-economic information.

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We found unusual digenean intramolluscan stages, sporocysts and cercariae, in gastropods Sulcospira dautzenbergiana (Morelet) (Caenogastropoda: Pachychilidae) from Southern Vietnam and named them Cercaria cattieni 1. These cercariae have a stylet and thus belong to the Xiphidiata. However, such combination of characters as extremely large body size and I-shaped excretory bladder has not been found before in any other xiphidiocercariae.

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Interaction and transformation of the mononuclear cationic dinitrosyl iron complex [Fe(SC(NH2)2)2(NO)2]+ (complex 1) upon binding with bovine serum albumin (BSA) have been explored using kinetic measurements, UV-Vis and fluorescence spectroscopy, and computational molecular modeling. BSA was found to bind up to five molecules of complex 1 per one protein molecule; as a result, the rate of NO release by complex 1 into solution decreases by a factor of 10. The binding constant of complex 1 with BSA measured by the quenching of intrinsic fluorescence of BSA is 5 × 105 М-1.

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COVID-19 has been spreading rapidly around the world since December 2019. The main goal of this study is to develop a more effective method for diagnosing and predicting the COVID-19 spread and to evaluate the effectiveness of control measures to reduce and stop the virus spread. To this end, the COVID-19 Decision-Making System (CDMS) was developed to study disease transmission.

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Digeneans of the family Brachycladiidae are cosmopolitan parasites restricted to marine mammals. Their life cycles are unknown. Phylogenetically, Brachycladiidae are closely related to Acanthocolpidae, parasites of marine teleost fishes.

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The iron(iii) complex [Fe(Hsemsal)(semsal)]·3H2O (1) (H2semsal - salicylaldehyde semicarbazone) has been synthesized and characterized by powder and single crystal X-ray diffraction, and magnetic susceptibility measurements. Crystal structure analysis showed that the complex forms neat stacks stabilized by hydrogen-bonding through water molecules and π-π interactions between phenolate rings of ligands. The complex does not exhibit spin-crossover phenomena and remains in the high-spin state down to 2 K.

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Neophasis anarrhichae (Nicoll, 1909) Bray, 1987, unlike the majority of acanthocolpid digeneans, has an abbreviated two-host life cycle. The reproduction of rediae, development of cercariae, and their transformation into unencysted metacercariae occur within the only intermediate host, the whelk Buccinum undatum. Normally, the metacercariae develop into sexual adults (maritae) and egg production starts when the infected whelk is eaten by a wolffish Anarhichas lupus.

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The DFT calculations of the spin crossover complex [FeIII(Sal2-trien)]+ (1) with the following classification of conformers of 1 were performed. The study shows that rearrangements of ethylene group orientation in a coordinated ligand lead to the stabilization of the high-spin or low-spin iron(iii) state.

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In the White Sea, the blue mussel Mytilus edulis occupies a wide range of biotopes and is associated with numerous symbiotic organisms. At some sites, mussel cover spreads continuously from the intertidal to the subtidal zone. We checked whether the patterns of infection by different associated organisms differed among the upper subtidal, zero-depth and lower intertidal zones at 3 sites in the Kandalaksha Gulf and the Onega Bay of the White Sea.

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This paper presents the results obtained from the study of the sustainable state between nature and human society on a global scale, focusing on the most critical interactions between the natural and anthropogenic processes. Apart from the conventional global models, the basic tool employed herein is the newly proposed complex model entitled "nature-society system (NSS) model", through which a reliable modeling of the processes taking place in the global climate-nature-society system (CNSS) is achieved. This universal tool is mainly based on the information technology that allows the adaptive conformance of the parametric and functional space of this model.

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