28 research outputs found

    A multiscale approach to evaluate the structure of diversity of Collembola in boreo-nemoral forests of the Russian Plain

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    Collembola is a group of numerous ubiquitous small soil-dwelling arthropods decomposing the plant residues. The study analyses the diversity structure of this group in mesic conditions of coniferous, mixed, and broad-leaved forests. Sample plots were located in three Protected Areas in the Moscow Region (Losiny Ostrov National Park and the Valuyevsky Forest Park) and Smolensk Region (Smolenskoe Poozerye National Park). In total, 70 species of Collembola were registered in the forest litter. Two Collembola species were of Asian origin, namely Appendisotoma stebayevae (noted in Europe for the first time) and Vertagopus asiaticus (the second record of this species in the study area). The number of species was close to the number of genera, indicating the allochthonous character of the forest fauna of Collembola of the central Russian Plain. A multiscale approach was applied for sampling design. This allowed us to assess the diversity of Collembola at various spatial scales: from 1 m to hundreds of kilometres. The study scheme included two regions, four localities, 12 sample sites, and 36 plots; the latter was 1 m2 (the smallest area unit). The data analysis was based on the concept of alpha-beta diversity accompanied by the additive partitioning method. The region (the largest area unit) was the most important factor in forming the species diversity. The type of forest litter (coniferous vs. broad-leaved) was less significant; the habitat heterogeneity factor made even a less contribution. On average, 1 m2 of forest litter comprised about a quarter of the entire list of Collembola species in the studied forests. The species richness of Collembola in the broad-leaved forests was more variable in space and in time compared to coniferous forests and mixed forests; a transitional pattern was observed. The species composition of Collembola varied between the seasons of the year by about a quarter when considering the same sites of coniferous and mixed forests. In broad-leaved forests of various areas, seasonal changes in species composition varied highly, from very pronounced to insignificant. The new concept of plant litter traits is discussed as a factor for affecting the patterns of the structure and dynamics of the Collembola species diversity

    MYOPATHY AS A DESTABILIZING FACTOR OF MEAT QUALITY FORMATION

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    This review paper is devoted to myopathy of slaughter animals and poultry, and examines a relationship between fast growth of muscle tissue in hybrid pigs, broiler chickens and turkey, and high frequency of detection of spontaneous or idiopathic myopathies. The development of myopathy reduces consumer and technological properties of meat, and leads to emergence of different pathological conditions (PSE or RSE meat, «destructured meat», «white» or «green» meat, punctate hemorrhage, «wooden breast» and others). Two types of myopathic conditions are examined: myopathies caused by stress in animals and nutritional myopathies, which contribution to meat quality deterioration seems to be determinative. It is shown that the basis of the mechanism of the myopathy development is the mechanism of the successive changes in muscle tissue: damage of cell membranes and release of mitochondrial calcium, which causes hypercontraction, dystrophic changes, atrophy and necrosis of muscle fibers. To alleviate the damaging effect of two types of myopathies, different substances-adaptogens (selenium, vitamin E, flavonoids and others) can be used. It is stated that the requirements of animals in adaptogens change with an increase in the indicators of their productivity.This review paper is devoted to myopathy of slaughter animals and poultry, and examines a relationship between fast growth of muscle tissue in hybrid pigs, broiler chickens and turkey, and high frequency of detection of spontaneous or idiopathic myopathies. The development of myopathy reduces consumer and technological properties of meat, and leads to emergence of different pathological conditions (PSE or RSE meat, «destructured meat», «white» or «green» meat, punctate hemorrhage, «wooden breast» and others). Two types of myopathic conditions are examined: myopathies caused by stress in animals and nutritional myopathies, which contribution to meat quality deterioration seems to be determinative. It is shown that the basis of the mechanism of the myopathy development is the mechanism of the successive changes in muscle tissue: damage of cell membranes and release of mitochondrial calcium, which causes hypercontraction, dystrophic changes, atrophy and necrosis of muscle fibers. To alleviate the damaging effect of two types of myopathies, different substances-adaptogens (selenium, vitamin E, flavonoids and others) can be used. It is stated that the requirements of animals in adaptogens change with an increase in the indicators of their productivity

    Combination Breeding and Marker-Assisted Selection to Develop Late Blight Resistant Potato Cultivars

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    (1) Background: Although resistance to pathogens and pests has been researched in many potato cultivars and breeding lines with DNA markers, there is scarce evidence as to the efficiency of the marker-assisted selection (MAS) for these traits when applied at the early stages of breeding. A goal of this study was to estimate the potential of affordable DNA markers to track resistance genes that are effective against the pathogen Phytophthora infestans (Rpi genes), as a practical breeding tool on a progeny of 68 clones derived from a cross between the cultivar Sudarynya and the hybrid 13/11-09. (2) Methods: this population was studied for four years to elucidate the distribution of late blight (LB) resistance and other agronomical desirable or simple to phenotype traits such as tuber and flower pigmentation, yield capacity and structure. LB resistance was phenotypically evaluated following natural and artificial infection and the presence/absence of nine Rpi genes was assessed with 11 sequence-characterized amplified region (SCAR) markers. To validate this analysis, the profile of Rpi genes in the 13/11-09 parent was established using diagnostic resistance gene enrichment sequencing (dRenSeq) as a gold standard. (3) Results: at the early stages of a breeding program, when screening the segregation of F1 offspring, MAS can halve the workload and selected SCAR markers for Rpi genes provide useful tools

    The Structure of Carbon Gels Obtained by Carbonization of Organic Xerogels Based on Larch Bark Tannins and Pine Cellulose

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    Впервые предложено получать углеродные гели путем карбонизации органических гелей, синтезированных золь-гель конденсацией формальдегида с таннинами коры лиственницы и целлюлозой сосны. По данным метода БЭТ, введение целлюлозы в состав органического таннин-формальдегидного геля меняет такие характеристики пористой структуры получаемых углеродных гелей, как удельная поверхность, общий объем пор, удельная поверхность микропор, объем микропор, объем мезопор, средний диаметр пор. Развитие пористой структуры углеродных гелей, полученных с использованием добавок растворенной целлюлозы (10 и 20 мас%), происходит в результате формирования мезопор со средним диаметром 22.83 и 21.54 нм. Введение порошка целлюлозного аэрогеля в исходный органический гель способствует формированию микропор в получаемом углеродном геле. Наиболее развитую микропористую структуру имеет углеродный гель, полученный карбонизацией органического таннин-целлюлозного геля, содержащего 20 мас% целлюлозного аэрогеля (удельная поверхность 754 м2/г, из них 80 % (606 м2/г) приходится на поверхность микропор). Методом сканирующей электронной микроскопии установлено, что морфологию поверхности углеродных гелей, получаемых карбонизацией органических таннин-целлюлозных гелей, можно регулировать путем вариации как концентрации целлюлозы, так и её состояния (раствор целлюлозы или порошок целлюлозного аэрогеля) при синтезе исходного органического геляFor the first time, it was proposed to obtain carbon gels by carbonization of organic gels synthesized by sol-gel condensation of formaldehyde with larch bark tannins and pine cellulose. According to the BET method, the introduction of cellulose into the composition of an organic tannin- formaldehyde gel changes such characteristics of the porous structure of the obtained carbon gels as specific surface area, total pore volume, micropore surface area, micro- and mesopore volume, and average pore diameter. The development of the porous structure of carbon gels obtained with the use of dissolved cellulose additives (10 and 20 wt%) occurs as a result of the formation of mesopores with an average diameter of 22.83 and 21.54 nm. The introduction of cellulose aerogel powder into the original organic gel promotes the formation of micropores in the resulting carbon gel. The most developed microporous structure has a carbon gel obtained by carbonization of an organic tannin-cellulose gel containing 20 wt% cellulose aerogel (specific surface 754 m2/g, of which 80 % (606 m2/g) relates to the surface of micropores). Using scanning electron microscopy, it was found that the surface morphology of carbon gels obtained by carbonization of organic tannin-cellulose gels may be controlled by varying both the concentration of cellulose and its state (cellulose solution or cellulose aerogel powder) during the synthesis of the initial organic ge

    Value Analysis of the Machine-Building Enterprise Repair Facilities Activities

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    This article is devoted to the problems of the organizational structure optimization by the method of Value Analysis (VA). The analysis of the control system is of particular relevance in modern conditions. The purpose of this article is to adapt the Value Analysis to the management structure with the possibility of increasing efficiency. VA is a universal and highly effective method for optimizing parameters and other design, technological, organizational, economic characteristics of products, works and services. The hypothesis of the possibility of applying the Value Analysis to the organization of the enterprise subdivision work is considered. The article examines the VA tools using the example of an enterprise's repair service. An organizational structural-element model of the object is being built. Decomposition of functions is carried out. According to the level criterion, the functions are classified into main and auxiliary ones. The significance and functional costs are determined. A functional-cost diagram is constructed, which allows highlighting the functions with the greatest deviations that need to be improved. The VA stages are accompanied by graphical illustrations and tables which allow us to clearly demonstrate the logic of the method application to the work of the enterprise division. As a result, the optimal concept of the organization of the machine-building enterprise structural unit is formed
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