Search

Global climate change might result in permafrost thaw and the formation of thermokarst landscapes that release long-term carbon stocks as greenhouse into the atmosphere, thereby initiating a positive climate feedback. These processes are mediated by biological activity, including by microbes, vascular plants and animals, whereas the role of invertebrates in thermokarst ecosystems remains poorly understood. We investigated the diversity and assemblage structures of zooplankton (mainly Copepoda, Cladocera), microbenthos (testate amoebae) and meio- (Copepoda and Cladocera) and macrozoobenthos (mollusks, crustaceans, insects and annelids) from a range of water bodies representing different stages of thermokarst lake formation in the southern part of the Lena River Delta (Central Siberia). Altogether, 206 species of testate amoeba, mollusk, crustacean, insect and annelid taxa were identified. A total of 60 species of macrozoobenthos (mainly insects) and 62 species of testate amoebae were detected in the water bodies of the Lena River Delta for the first time. The species richness of zooplankton and meio- and macrozoobenthos was greater in the large thermokarst lakes than in the polygonal ponds due to the freezing of the latter in the winter. In contrast, the species richness of protists was higher in the polygonal ponds, which was related to the habitat preferences of testate amoebae. Fish grazing strongly affected the macrobenthos assemblages but not the smaller-sized organisms. Water acidity and temperature were the main environmental drivers of the assemblage structure of testate amoeba and microcrustacean. The species structure of the macroinvertebrate assemblages was significantly explained by water acidity, permafrost depth and size of the water area. It means that small size organisms with their short generation times are sensitive to more dynamic factors such as temperature and may serve as indicators of ecosystem changes due to global climate warming. In contrast, large size organisms are affected by driven factors that appear during thermokarst lakes formation and permafrost degradation. [ABSTRACT FROM AUTHOR]

A better understanding of past climate change is vital to our ability to predict possible future environmental dynamics. This study attempts to investigate the dynamic features of the temporal variability of peat humification, water table depth and air temperature by analyzing palaeoecological data from the Valdai Uplands region (Central European Russia). The regression analysis revealed the presence of a periodicity of about 6000 years in the reconstructed peat humification timeseries. Nonlinear analysis showed that humification time variability, water table depth and air temperature exhibit persistent long-range correlations of 1/f type. This indicates that a fluctuation in these variables in the past is very likely to be followed by a similar one in the future, but is magnified by 1/f power-law. In addition, it dictates that humification, water table depth and temperature are key parameters of a system that implies the existence of a special structure, such as self-organized criticality, operating close to a minimum stability configuration, and achieves it without any fine adjustment by external forcing. These conclusions point to new avenues for modeling future ecosystem disturbances and, in particular, for predicting relevant extreme events. [ABSTRACT FROM AUTHOR]

In 2018, the faunas of Cladocera and Copepoda of four mountain Sphagnum peatlands in the Republic of North Ossetia and five in the Republic of Kabardino-Balkaria, Caucasus, Russia, were studied. For each area, species complexes peculiar both to the central part of the secondary water body and to the surrounding Sphagnum floating mat, at the edge of the water, were described. Altogether, 31 species of microcrustaceans were found in the material collected. Among them, two species of Cladocera and eight species of Copepoda were recorded from mountain water bodies of the North Caucasus for the first time. Montane Sphagnum peatlands were shown to be an outpost of northern species distributions, as confirmed by finding two Copepoda species typical of more northerly regions. The abundance of microcrustaceans in floating Sphagnum mats was often tens of times higher than in the water column. The habitat type, seasonality, latitude, longitude, altitude, temperature, acidity, and mineralization combined were shown to explain only 32.3% of variations in the species complexes. This indicates a complex factor regulation of the community structure in high-altitude conditions. [ABSTRACT FROM AUTHOR]

The Kamchatka Peninsula in the far east of Russia is a substantial landmass that is poorly documented in terms of most elements of biodiversity. Here we provide the first study of modern assemblages of testate amoebae, a widespread group of protists that are particularly abundant in soils. We present a data set of 78 widely distributed samples, including forest, fen, scrub and bog habitats. Testate amoebae are abundant and diverse across Kamchatka with 119 taxa identified. The assemblage is primarily composed of widespread taxa, but rarer occurrences such as Cyclopyxis puteus hint at important biogeographical differences that will require confirmation with molecular data. Assemblages from mineral soils are significantly different from those of peatlands with the former characterized by small idiosome taxa and the latter by larger taxa, often with secretion tests. Water table depth explained significant variance in the peatland samples, supporting the use of testate amoebae in palaeoecological studies. This study adds to our knowledge of the biodiversity of Kamchatka and the global biogeography of protists, and it paves the way for palaeoecological studies to understand long‐term environmental change in this region. [ABSTRACT FROM AUTHOR]

The present studies have examined the effect of potato starches treated with amylase B.licheformis (Bl) (laboratory sample) or Amylosubtilin® (AM) (Berdsk Factory of Biological Preparations (now: Sibbiofarm), Russia) in different concentrations on the quality of Slavic skim milk drink Varenets made from baked milk. The baked milk is milk heated to 98 °C for 3 hours, it has a sweet aroma and taste and creamy hue. The presence of enzymemodified potato starches (Bl or AM) has been found to promote the activation of lactic acid fermentation, the accumulation of exopolysaccharides, and such stabilized products have a higher viscosity, a lower percentage of syneresis compared to the control sample. The antioxidant capacity of the Varents samples after fermentation was evaluated by two assays: analysis of radical capture activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH •); and the ability to restore Fe + 3 (Iron Reduction Antioxidant Ability Assay, FRAP). All Varentz samples showed different values for DPPH, FRAP assays depending on the starches used. The Introduction of pre-fermented starches into defatted jam promotes formation of enhanced antioxidant properties of milk product. The use of starches modified with enzymes improves sensory characteristics, in particular, as a fat imitator, formsfull taste of the drink. [ABSTRACT FROM AUTHOR]

The relevance of the study is due to the development of the Russian insurance market, and, accordingly, changes in the insurance staff qualifying requirements. In modern Russian Federation three main complex factors determine this change: technological, organizational, juristic development of the insurance market, development of the educational system and new realness of the labour market. Since 2012 - 2015 the labour market innovations are concern with the professional standards, but especially in the insurance market their implementation is too hard compare another financial and industry sectors. The second factor is new forms of education results, content and structure development of educational system: for example, Master Program "Insurance Business" received the first certificate of professional public accreditation among all Russian educational organizations and programs (this is once more paradox, considering a low demand for the profession). Finally, of course, the insurance market, which defines the functional content and requirements for specialists. In this regard, the article is aimed at the confirmation of the objectivity changes in requirements for insurance staff, identification the opportunities, the development proposals of the insurance staff profession, the main changes in the requirements for specialists. [ABSTRACT FROM AUTHOR]

Testate amoebae are important components of benthic communities in freshwater lakes, where they play an essential role in decomposer food webs. They are used widely in paleoecological investigations because of their high taxonomic diversity, well-defined ecological preferences and decay-resistant tests. Studies of testate amoeba assemblages in lake surface sediments are necessary to better understand lake ecosystem function and improve the use of these organisms as bio-indicators in paleoecology. This study explored the use of testate amoebae as proxies for inferring past water level in freshwater lakes, and expanded upon the limited body of research into lake testate amoebae in Russia. Our results indicate that species composition of testate amoeba assemblages in the lakes was typical for such biotopes, with most of the species belonging to the genera Difflugia, Centropyxis, Arcella and Euglypha. Analysis of variation of testate amoebae along a water-depth gradient showed that three assemblage types could be distinguished: shallow-water (0–4.5 m), intermediate-water-depth (4.5–20.5) and deep-water (20.5–33 m). Deep-water assemblages did not contain any unique taxa and were dominated by eurybiotic and planktonic species. Species diversity was highest in the intermediate-water-depth assemblages and lowest in deep-water ones. Although variations in testate amoeba assemblages across water depth in freshwater lakes are complex and context-dependent, there are clear patterns in species composition and diversity, which can be used to infer past lake water levels. Future studies on the effect of water depth on testate amoeba assemblages in diverse types of freshwater lakes should increase the utility of the method. [ABSTRACT FROM AUTHOR]

Climate change and human activity considerably influenced the temperate European deciduous forests through the Holocene, with the anthropogenic impacts being detected even in currently protected areas. This paper is focused on the area of the Kaluzhskiye Zaseki Nature Reserve, which contains remnants of primary broadleaved forests in central European Russia. Here, we present a new multi-proxy record including pollen, plant macrofossils, charcoal, loss on ignition and radiocarbon dating from the Mochulya peatland supplemented by 14 radiocarbon dates of charcoal fragments from soil pits in the study area. The results show that Mochulya peatland was a fen throughout the most of the time it existed. During the last 4200 cal yr BP the study area was occupied by broadleaved forests of Quercus, Ulmus, and Tilia. Picea became relatively abundant after 2300 cal yr BP. Despite the long-term human impact, vegetation fragments of these forests have persisted in the area until the present. Three main periods of deforestation and frequent fires were identified: 3700–3200 cal yr BP, 2000–1600 cal yr BP (the Early Iron Age) and 1000–400 cal yr BP (the Medieval Period). Whereas human-induced vegetation changes were apparent during the last two periods, vegetation dynamics during 3700–3200 cal yr BP were likely caused, at least in part, by climatic factors. [ABSTRACT FROM AUTHOR]

Two bacterial strains Ach-343 and Opo-235 were isolated, respectively from nodules of Miocene-Pliocene relict legumes Astragalus chorinensis Bunge and Oxytropis popoviana Peschkova originated from Buryatia (Baikal Lake region, Russia). For identification of these strains the sequencing of 16S rRNA (rrs) gene was used. Strain Opo-235 belonged to the species Mesorhizobium japonicum , while the strain Ach-343 was identified as M. kowhaii (100 and 99.9% rrs similarity with the type strains MAFF 303099T and ICMP 19512T, respectively). Symbiotic genes of these strains as well as some genes that promote plant growth (acdS , gibberellin- and auxin-synthesis related genes) were searched throughout the whole genome sequences. The sets of plant growth-promoting genes found were almost identical in both strains, whereas the sets of symbiotic genes were different and complemented each other with several nod , nif , and fix genes. Effects of mono- and co-inoculation of Astragalus sericeocanus , Oxytropis caespitosa , Glycyrrhiza uralensis , Medicago sativa , and Trifolium pratense plants with the strains M. kowhaii Ach-343 and M. japonicum Opo-235 expressing fluorescent proteins mCherry (red) and EGFP (green) were studied in the gnotobiotic plant nodulation assay. It was shown that both strains had a wide range of host specificity, including species of different legume genera from two tribes (Galegeae and Trifolieae). The effects of co-microsymbionts on plants depended on the plant species and varied from decrease, no effect, to increase in the number of nodules, nitrogen-fixing activity and plant biomass. One of the reasons for this phenomenon may be the discovered complementarity in co-microsymbionts of symbiotic genes responsible for the specific modification of Nod-factors and nitrogenase activity. Localization and co-localization of the strains in nodules was confirmed by the confocal microscopy. Analysis of histological and ultrastructural organization of A. chorinensis and O. popoviana root nodules was performed. It can be concluded that the strains M. kowhaii Ach-343 and M. japonicum Opo-235 demonstrate lack of high symbiotic specificity that is characteristic for primitive legume-rhizobia systems. Further study of the root nodule bacteria having complementary sets of symbiotic genes will contribute to clarify the evolutionary paths of legume-rhizobia relationships and the mechanisms of effective integration between partners. [ABSTRACT FROM AUTHOR]

Currently, most oil fields and reservoirs in Russia have entered a late stage of development: the average field waret cut of many large deposits is more than 80 %, and for the unique - 92 %. The encroachment of production horizons of reservoirs causes serious complications in oil recovery, collection and preparation processes associated with the formation of water-oil emulsions. Due to the presence of a dispersed phase and a strong oil-water adsorption boundary layer oil emulsions have a higher viscosity, that causes serious complications during oil recovery and collection, and the presence of natural surfactants in the oil gives the majority of emulsions a high resistance. The degree of de-emulsification depends on many technological factors, the main of which is the addition of demulsifiers during thermochemical dehydration of oil. At the same time, it should be noted that the use of demulsifiers is a necessary, but not a sufficient condition for high-quality oil treatment, for this it is necessary to create a highly efficient technology as a process in general. One of the directions of the complex approach can be the use of composite demulsifiers at all stages of the technological process. This approach should be based on the study of the mechanisms of the effect of chemical reagents on colloid-chemical properties and the structure of oil disperse systems. The results of this work show that substances with high surface-active and wetting properties intensify the coalescence of water globules during de-emulsification and reduce the strength of the interfacial adsorption layer at the «oil-water» boundary. The combination of surface-active, wetting and rheological properties of composite demulsifiers promotes high adsorption of the reagent on the interphase surface, displacement of emulsion stabilizers from the adsorption layer surface, that leads to the rapid breakage of highly stable water-oil emulsions. [ABSTRACT FROM AUTHOR]

Understanding the long-term ecological dynamics of boreal forests is essential for assessment of the possible responses and feedbacks of forest ecosystems to climate change. New data on past forest dynamics and peatland development were obtained from a peat sequence in the southern Valdai Hills (European Russia) based on pollen, plant macrofossil, micro-charcoal, peat humification, and testate amoeba analyses. The results demonstrate a dominance of broadleaved forests in the study area from 7000–4000 cal yr BP. Picea was initially a minor component of this forest but increased in cover rapidly with climatic cooling beginning at 4000 cal yr BP, becoming the dominant species. Broadleaved species persisted until 900 cal yr BP, with evidence for intensified felling and forest management over recent centuries. Over the last four hundred years there is evidence for widespread paludification and the establishment of Picea-Sphagnum forests. These data demonstrate how modern wet woodlands have been shaped by a combination of climatic and anthropogenic factors over several millennia. The results also demonstrate the value of a multiproxy approach in understanding long-term forest ecology. [ABSTRACT FROM PUBLISHER]

Despite their huge extent, the peatlands of Russia are an under-exploited source of data on palaeoenvironmental change. We investigated the Holocene history of Staroselsky Moch, an ombrotrophic peatland in the Tver Region of European Russia by analysis of testate amoebae, peat physical properties, plant macrofossils and pollen. The peatland developed through a classic hydroseral succession in the early Holocene with a sharp decline in mineral input to 6200 cal. BC followed by an abrupt transition from fen to bog vegetation around 5500 cal. BC. Through the Holocene, the peatland has accumulated carbon at a mean apparent rate of 21.5 g C m−2 yr−1 suggesting that carbon accumulation rates in peatlands of European Russia lie close to the global average, and contrasting with a short sequence of eddy-covariance data which implies a net loss of carbon. The testate amoeba record shows considerable variability which may be driven by climate, but changes are not well replicated in the macrofossil or pollen data. We tentatively infer (1) a phase of early Holocene warming commencing around 7200 cal. BC, (2) dry peatland surface conditions c. 3700–3900 cal. BC, (3) a shift to wetter conditions from c. 3900 cal. BC, and (4) drier conditions from c. 400 cal. BC onwards. More robust and precise hydroclimatic reconstructions for this region will require the development of a regional transfer function and the replication of results between cores and sites. [ABSTRACT FROM AUTHOR]

In order to better understand the distribution patterns of terrestrial eukaryotic microbes and the factors governing them, we studied the diversity partitioning of soil testate amoebae across levels of spatially nested habitat hierarchy in the largest European old-growth dark coniferous forest (Pechora-Ilych Biosphere Reserve; Komi Republic, Russia). The variation in testate amoeba species richness and assemblage structure was analysed in 87 samples from six biotopes in six vegetation types using an additive partitioning procedure and principal component analyses. The 80 taxa recorded represent the highest value of species richness for soil testate amoebae reported for taiga soils so far. Our results indicate that testate amoeba assemblages were highly aggregated at all levels and were mostly controlled by environmental factors rather than dispersal processes. The variation in species diversity of testate amoebae increased from the lowest to the highest hierarchical level. We conclude that, similarly to macroscopic organisms, testate amoeba species richness and community structure are primarily controlled by environmental conditions within the landscape and suggest that metacommunity dynamics of free-living microorganisms are driven by species sorting and/or mass effect processes. [ABSTRACT FROM AUTHOR]

Abstract: Simulation codes for the spectra of heavy implanted nuclei, applications for online data visualization and real time PC-based algorithms are considered. Special attention is paid to the application of real time techniques for radical suppression of background products in heavy-ion-induced nuclear reactions at the U-400 cyclotron of the Flerov Laboratory of Nuclear Reactions. The detection system of the Dubna gas-filled recoil separator (DGFRS) is also briefly described. Calculated heavy recoil spectra are compared with those measured in heavy-ion-induced nuclear reactions. [Copyright &y& Elsevier]

Discusses the objectives of the Program for the Support of Entrepreneurship in Russia. Development of entrepreneurial activity; Creation of equal starting opportunities and conditions for entrepreneurship; Organization of the entrepreneurship.

Peatlands are remarkable for their specific biodiversity, crucial role in carbon cycling and climate change. Their deposits preserve organism remains that can be used to reconstruct long-term ecosystem and environmental changes as well as human impact in the prehistorical and historical past. This study presents a new multi-proxy reconstruction of the peatland and vegetation development investigating climate dynamics and human impact at the border between mixed and boreal forests in the Valdai Uplands (the East European Plain, Russia) during most of the Holocene. We performed plant macrofossil, pollen, testate amoeba, Cladocera, diatom, peat humification, loss on ignition, carbon and nitrogen content, δ13C and δ15N analyses supported by radiocarbon dating of the peat deposits from the Krivetskiy Mokh mire. The results of the study indicate that the wetland ecosystem underwent a classic hydroserial succession from a lake (8300 BC–900 BC) terrestrialized through a fen (900 BC–630 AD) to an ombrotrophic bog (630 AD–until present) and responded to climate changes documented over the Holocene. Each stage was associated with clear changes in local diversity of organisms responding mostly to autogenic successional changes during the lake stage and to allogenic factors at the fen-bog stage. The latter can be related to increased human impact and greater sensitivity of peatland ecosystems to external, especially climatic, drivers as compared to lakes. [ABSTRACT FROM AUTHOR]

In Russia, tetramethylthiuram disulfide (TMTD) is a fungicide widely used in the cultivation of legumes, including the pea (Pisum sativum). Application of TMTD can negatively affect nodulation; nevertheless, its effect on the histological and ultrastructural organization of nodules has not previously been investigated. In this study, the effect of TMTD at three concentrations (0.4, 4, and 8 g/kg) on nodule development in three pea genotypes (laboratory lines Sprint-2 and SGE, and cultivar 'Finale') was examined. In SGE, TMTD at 0.4 g/kg reduced the nodule number and shoot and root fresh weights. Treatment with TMTD at 8 g/kg changed the nodule color from pink to green, indicative of nodule senescence. Light and transmission electron microscopy analyses revealed negative effects of TMTD on nodule structure in each genotype. 'Finale' was the most sensitive cultivar to TMTD and Sprint-2 was the most tolerant. The negative effects of TMTD on nodules included the appearance of a senescence zone, starch accumulation, swelling of cell walls accompanied by a loss of electron density, thickening of the infection thread walls, symbiosome fusion, and bacteroid degradation. These results demonstrate how TMTD adversely affects nodules in the pea and will be useful for developing strategies to optimize fungicide use on legume crops. [ABSTRACT FROM AUTHOR]

Abstract Using the territory of the Orlovskoye Polesye National Park as a case study within the catchment basin of the Oka River (Mid-Russian Uplands, Oryol Region, Russia), we obtained palaeoecological data for studying response of forest landscapes within the forest-steppe ecotone to climate change and human impact through the Late Holocene. The paper presents reconstruction of environmental change on a local to regional scales based on plant macrofossil, spore-pollen and testate amoeba records from a peat core along with reconstruction of woodland coverage inferred from pollen data. Over the past 4000 years, the total woodland coverage has fluctuated insignificantly, ranging from 38 to 52%, while the structure of the forest has changed radically. Prior to 1500 cal. yr BP, both birch-pine and mixed temperate deciduous forests of oak, elm, ash and lime with Scots pine and well-developed shrub understory of hazel and alder grew in the region. The subsequent agricultural colonization of the territory led to a reduction of a broadleaved trees in forest stands since 1500 cal. yr BP. During the last few centuries, human activity largely associated with cutting/burning trees and farming favored the expansion of secondary forests dominated by birch. [ABSTRACT FROM AUTHOR]

• Estimates of temporal variation may resolve the "everything is everywhere" dispute. • Seasonal species turnover comprises up to 50 % of the total species diversity. • Assemblages are more diverse and heterogeneous in spring than in autumn. • Assemblages are considerably controlled by substrate moisture in summer and autumn. • Hydrophilic testate amoebae in spring are replaced by xerophilic species in autumn. Understanding the spatial and temporal variation in protist communities is essential for comprehensive studies on diversity and biogeography, yet most research focuses on either spatial or temporal processes, ignoring their combined effects. Here we use an additive partitioning approach to estimate the contribution of temporal and spatial components to the total taxonomical (morphospecies) diversity of testate amoebae in a swampy forest (the forest-steppe zone, Russia) during a snow-free season (from April to November). Testate amoebae have been chosen as model organisms for the study because they are a diverse and abundant group of protists that play important roles in soil communities mostly as consumers in decomposer food webs. Our results indicate that seasonality considerably contributed to the variation in the total species richness (γ) of both live and empty shell assemblages of testate amoebae (48 and 38 %, respectively). The beta component of species richness related to the spatial variation among sampling plots explained 22 % of γ-diversity in live assemblages and 28 % in empty shell assemblages. Beta diversity (both as species richness and species composition) decreased towards the end of the snow-free season. Spring assemblages were dominated by hydrophilous species of testate amoebae, whereas xerophilic species were more abundant in autumn. Our results imply that the snowmelt phase could be an important factor setting the heterogeneity of testate amoeba assemblages in the early spring, whereas in the rest of snow-free season the assemblages were considerably controlled by substrate moisture. Overall, temporal sampling is essential for adequate estimates of species diversity of soil-dwelling testate amoebae. [ABSTRACT FROM AUTHOR]

Background: Recent studies have suggested that para-Hisian atrial tachycardia (AT) can be successfully ablated from the right atrium (RA), left atrium (LA), or noncoronary cusp (NCC) in the aorta; however, the best approach remains unclear., Objective: This study aimed to compare different approaches to radiofrequency catheter ablation (RFCA) of para-Hisian AT., Methods: We retrospectively analyzed 68 consecutive patients (49[72%] women; mean age 61 ± 13 years) treated with RFCA for this type of AT. Mapping of the RA (n = 68), LA (n = 21), and NCC (n = 52) was performed during AT to identify the earliest activation site and to apply RFCA., Results: RFCA successfully terminated AT in the RA in 13 of 28 patients (46.4%), in the LA in 4 of 16 patients (25.0%), and in the NCC in 46 of 52 patients (88.5%) after 1 procedure (P < .05). Atrioventricular block occurred only during RFCA in the RA in 4 of 28 patients (14.3%). After a mean follow-up of 33.5 ± 25.4 months, AT recurrence was observed in 5 of 13 patients (38.5%) ablated in the RA, 1 of 4 (25.0%) ablated in the LA, and 2 of 46 (4.4%) ablated in the NCC (P < .05). RFCA in the LA was effective only if the local activation time (LAT) was earlier than that in the RA. RFCA in the NCC was successful regardless of the LAT (P < .05)., Conclusion: Mapping and ablation in the NCC should be always considered in cases of AT originating from the His bundle region, regardless of the LAT., (Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Community structure of zoohydrobionts in the lake affected by chemical weapon destruction was studied for the first time. Low pH favored species specific to acidic water bodies as well as bidominant zooplankton community. The long-term effects of chemical pollution determined the stage of community succession, namely, the absence of the key predator (fishes), abundance of detritus consumers in the zoobenthic community (dipteran larvae), diversity of amphibiotic insects, and low species diversity in the zooplankton community with the prevalence of cladocerans and rotifers. Unbalanced composition of higher trophic levels results in an unstable functioning of the lake and accumulation of significant amounts of detritus, which is utilized by the abundant microzoobenthic component of the ecosystem.