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The main objectives of this publication are: 1) to attract the attention of energy specialists to the problems of reliability and electrical safety of 6-10 kV overhead electrical networks with isolated neutral, operating in conditions of single-phase insulation damage; 2) substantiation of the feasibility of introducing a fundamentally new way to improve the efficiency of 6-10 kV distribution networks, based on the resonanceless limitation of the single-phase ground fault current arising from the breakdown of the insulator and the use of its own infrastructure of the electrical network for remote identification of the place of its occurrence. The expediency of including a nonlinear surge suppressor between the traverse and the grounding outlet of the reinforced concrete support is confirmed by the positive results of experimental studies carried out on the basis of high-voltage testing laboratories of IDGC of Center PJSC - Orelenergo and EnerGarant LLC. The use of deductive analysis allowed the authors to select a reliable and affordable electrical insulating material installed between the support and the traverse, as well as to formulate the main requirements for it, including taking into account weather and climatic factors. The analysis of various methods of transmitting information about the place of occurrence of the insulator damage made it possible to establish the predominant advantage of a wired communication channel using its own 6-10 kV electric network infrastructure. The authors have developed an original circuitry solution that provides remote identification of the insulator damage location using a thyristor shunting the nonlinear surge suppressor, according to a given switching algorithm, and also provides local identification of the insulator breakdown by means of special signaling devices with volatile power supply. It is expected that the proposed method, with relatively low investment, will significantly reduce the level of accidents and electrical hazards in overhead distribution networks of 6-10 kV, as well as minimize the costs associated with their operation and undersupply of electrical energy.

The paper focuses on the concept of “smart city”, its main approaches, and essential features. The authors state that the concept is still not well defined and there are many perspectives on it in the scholarly literature. The total of five essential characteristics of “smart cities” are discussed: “smart environment”, “smart economy”, “smart mobility”, “smart management”, and “smart people”. The authors also review the necessary infrastructure a city should have in order to be considered “smart”.

The functional traits of soil protists have been employed in ecological research to enhance comprehension of the underlying mechanisms of ecological processes. Among the numerous soil protists, testate amoebae emerge as a prominent and abundant group, playing a pivotal role in soil micro-food webs. Furthermore, they are regarded as valuable bioindicators for environmental monitoring and palaeoecological studies due to their sensitivity to environmental changes. We screened 372 testate amoebae species widely distributed across Northern Holarctic realm and collected trait data, representing the morphological and feeding characteristics of testate amoebae. The dataset would provide valuable basis for investigation of the functional diversity and ecological roles of testate amoebae, thus facilitating further research on soil protist communities and ecosystem dynamics., (© 2024. The Author(s).)

The relationship between species diversity and spatial scale is a central topic in spatial community ecology. Latitudinal gradient is among the core mechanisms driving biodiversity distribution on most scales. Patterns of β-diversity along latitudinal gradient have been well studied for aboveground terrestrial and marine communities, whereas soil organisms remain poorly investigated in this regard. The West Siberian Plain is a good model to address diversity scale-dependence since the latitudinal gradient does not overlap with other possible factors such as elevational or maritime. Here, we collected 111 samples following hierarchical sampling (sub-zones, ecosystem types, microhabitat and replicate samples) and performed multi-scale partitioning of β-diversity of testate amoeba assemblages as a model of study. We found that among-ecosystem β-diversity is a leading scale in testate amoeba assemblages variation. Rare species determine β-diversity at all scale levels especially in the northern regions, where rare taxa almost exclusively accounted for the diversity at the ecosystem level. β-Diversity is generally dominated by the turnover component at all scales in lower latitudes, whereas nestedness prevailed at among-ecosystem scale in higher latitudes. These findings indicate that microbial assemblages in northern latitudes are spatially homogeneous and constrained by historical drivers at larger scales, whereas in southern regions, it is dominated by the turnover component both at the microhabitat and ecosystem scales and therefore determined by recent vegetation and environmental heterogeneity. Overall, we have provided the evidence for the existence of negative latitudinal gradient for among-ecosystem β-diversity but not for among-microhabitat and among-sample β-diversity for terrestrial testate amoeba communities., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Testate amoebae are a polyphyletic group of unicellular eukaryotic organisms that are characterised by a rigid shell and inhabit mostly freshwater and terrestrial ecosystems. They are particularly abundant in peatlands, especially in Sphagnum -dominated biotopes. Peatland hydrology is the most important influence on testate amoebae communities. The good preservation of the shells in peat deposits and their response to hydrological regime changes are the principles for palaeohydrological reconstructions. Any changes in the water balance of mires should be expected to have far-reaching effects on biogeochemical cycles, productivity, carbon dioxide and methane exchange., New Information: This paper presents a dataset (Darwin Core Archive - DwC-A) on the distribution of Sphagnum -dwelling testate amoebae in nine mires located in the forest-steppe subzone of the East European Plane. The dataset includes information about 86 taxa belonging to 29 genera and contains 3,123 occurrences of 49,874 individuals. The following environmental variables are provided: microtopography, oxidising and reducing potential, total mineralisation, substrate temperature, acidity, substrate wetness and water table depth. These data might be used for biogeographical and palaeoecological studies, including quantitative reconstructions., (Nailia M. Saldaeva, Kirill V. Babeshko, Viktor A. Chernyshov, Anton S. Esaulov, Alexander A. Komarov, Nikita R. Kriuchkov, Natalia G. Mazei, Damir A. Saldaev, Tamara G. Stojko, Andrey N. Tsyganov, Yuri A. Mazei.)

Elevation gradients have been useful to study distributional patterns of soil organisms since the time of Humboldt but only recently these patterns have been studied for soil microorganisms. Here we report the results on species diversity and composition of soil- and moss-dwelling testate amoeba assemblages along a 1400 m elevation gradient (904-2377 m a.s.l.) on Mount Fuji (Japan) from temperate forest to alpine vegetation. In total, 95 testate amoeba taxa belonging to 29 genera were identified. The core of testate amoeba assemblages was formed by ubiquitous species such as Trinema lineare, Euglypha laevis, Cryptodifflugia oviformis, and Trinema complanatum. However, several taxa with limited geographic distribution were also observed (e.g., Centropyxis latideflandriana, C. stenodeflandriana, Plagiopyxis cf. barrosi, Heleopera rectangularis, and Distomatopyxis couillardi). Species diversity indices (species richness and Shannon's index) were characterised by bell-shaped patterns peaking at ∼ 1700 m in the subalpine mixed conifer-deciduous forest. The species composition of testate amoeba assemblages was best explained by the vegetation types which accounted for 12.3% of the total variation. Overall, these findings indicate that elevation effects on species composition of testate amoeba assemblages are strongly mediated by vegetation., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

The genus Euglypha contains the largest number of filose testate amoeba taxa which were mainly described based on the morphological characteristics of shells. Despite the increasing amount of molecular data, the phylogenetic relationships within the genus Euglypha remain unresolved. In this work we provide new data on SSU rRNA gene sequences, light and electron microscopy for the two euglyphid species Euglypha bryophilaBrown, 1911 and Euglypha cristataLeidy, 1874. Both species are characterised by the presence of a turf of spines on the aboral pole of the shells but differ in shell cross sections (elliptical and circular, respectively). A newly revealed feature of E. bryophila is a three-lobed thickening at the anterior margin and an elongated lobe at the posterior margin of apertural plates. The phylogenetic analysis shows that the species group together with the previously sequenced taxa of the genus Euglypha according to the shell cross-section. The subdivision of the genus based on the shell symmetry may reflect evolutionary trends to complication of the shell from radial to biradial symmetry. We also suggest that the shape of the anterior thickening of apertural plates and the lobe at the posterior margin can be used to distinguish Euglypha at the species level., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

The review is devoted to hypercholesterolemia which is one of the leading risk factors for IHD. By its origin it can be primary and secondary. Three major mechanisms of primary hypercholesterolemia in humans are discussed. They are: low activity of LDL receptors, reduced affinity of LAL for receptors and overproduction of lipoproteins containing apo B. Depending on mechanism nonidentical molecular defects leading to cholesterol imbalance in cells or in circulating lipoproteins are occurred. The understanding of the nature and mechanisms of hypercholesterolemia development is of great clinical value, because having determined molecular defect and using drugs combinations the majority of patients are a success to have their lipids normal. Only in the case of homozygous familial hypercholesterolemia medicamentous treatment becomes secondary and the principal therapeutic methods are plasmapheresis or selective LDL apheresis. Gene therapy as a method of homozygous familial hypercholesterolemia correction is in forthcoming future.

Several men were examined for association between restriction fragment length polymorphism (RELP) Xba I (exon 26) number of tandem repeats in 3'-hypervariable region of the apolipoprotein-B gene and serum levels of cholesterol and triglyceride. These two types of polymorphism were studied. An association of the Xba I site and alleles containing more repeats in the 3'-hypervariable region with higher cholesterol and triglyceride was observed. 32 patients with CHD aged 24-56 years were examined. All the patients are males with clinical picture of CHD (stable angina pectoris of II-III functional classes) and dyslipoproteinemia of II a, II b and IV types by D. S. Fredrickson. Xba-I polymorphism of apo-B gene was detected by DNA polymerase reaction method. The following Xba-I genotypes were distinguished: X1X1 (absence of Xba I site); X1X2 (heterozygosity on Xba I site) and X2X2 (homozygosity on Xba-I site). Lipantil (fenofibratte) was prescribed in a dose of 300 mg daily after meals (100 mg three times a day). Data obtained show that DNA polymorphism of apo-B gene not only influences plasma lipids concentration but also determines effectiveness of hypolipidemic therapy. Hypolipidemic effect of lipantil depends on Xba-I site presents in apo-B gene and is significantly expressed in homozygous patients with X1X1 genotype.

With a purpose to study the state of platelet haemostasis and vasoactive prostanoids system 78 patients with ischemic heart disease aged 28 to 59 years were examined. Among them there were 22 patients with "isolated" hypo-alpha-cholesterolemia and 14 patients who had hypo-alpha-cholesterolemia combined with hypertriglyceridemia (HTG). The data obtained show that hypo-alpha-cholesterolemia is accompanied by platelet disorders aggravation and characterized by activated platelet percentage growth. There is a reverse relationship between alpha-cholesterol plasma level and activated platelet percentage (r = -0.52). There is a direct relationship between high-density lipoprotein cholesterol plasma level and concentration of stable prostacyclin metabolite (6-keto-PGF1 alpha) in plasma (r = 0.64). Hypo-alpha-cholesterolemia in combination with HTG is characterized by more significant disorders in prostacyclin-thromboxane system consisting in an increase of plasma thromboxane system consisting in an increase of plasma thromboxane A2 concentration (p < 0.001) and a decrease of 6-keto-PGF1 alpha plasma level (p < 0.05). An inverse apolipoprotein A-1 plasma level (r = -0.48) has been revealed in the group of patients who had hypo-alpha-cholesterolemia combined with HTG.

The paper presents a clinical and genealogical characterization of 50 probands suffering from coronary heart disease concurrent with various lipid metabolic disturbances and 211 first-degree relatives whose data have been obtained from the probands' histories while making up their pedigrees. The prevalence of atherosclerosis among the first-degree relatives has been demonstrated to be related to the nature of lipid metabolic disturbances in a proband. Some dyslipoproteinemias in the proband have been characterized by early onset of coronary heart disease, stroke, and their grave course in close relatives.

Recent data and concepts on the structure and functioning of apolipoprotein genes as well as on the role of hereditary factors in pathogenesis of atherosclerosis are reviewed. The most important variants of inherited disorders in the system of apolipoproteins promoting the development of atherosclerosis are considered. Special attention is paid to the RFLP of apolipoprotein genes which serves as a peculiar genetic background, increasing probability of the atherosclerosis development in certain individuals.

In an 8-month-old baby, one-stage correction of an atrial septal defect, multiple right and left atrial aneurysms and non-paroxysmal ectopic right atrial tachycardia was performed. An ectopic focus of atrial tachycardia was localized by a pre- and intraoperative electrophysiological study. Postoperatively, the patient's clinical status improved significantly.