139 research outputs found

    Calculation of the formation of normal cracks in a reinforced concrete element based on the deformation theory of plasticity of concrete by G.A. Geniev

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    The authors present a refined method of determining the moment of cracking in reinforced concrete bar constructions using the diagram of deformation of concrete built on the basis of the deformation theory of plasticity by G.A. Geniev in which the stress and strain invariants of concrete are linked by nonlinear dependences. In the resulting defining equations, the hypothesis of flat sections, as well as the premise of reaching the limit values of concrete deformations on the stretched fibers of the cross-section are used. Stresses in concrete are determined through deformation values in accordance with the nonlinear deformation diagram of concrete. On the basis of the assumptions accepted, analytical dependences for determining the moment of cracking in the sections of bending elements with single and double reinforcement have been acquired. The formulas obtained were used in the analysis of various factors influence on crack resistance of bendable reinforced concrete elements. It was found out that the moment of crack formation practically does not change when percentage of reinforcement of longitudinal tensile or compressed reinforcement changes. The most effective method of crack resistance improvement is the increase of concrete strength. The proposed methodology is verified by comparison with experimental results on reinforced concrete prototypes. It is concluded that the use of the diagram of nonlinear deformation of concrete on the basis of the theory of plasticity by G.A. Geniev allows to estimate more strictly the crack resistance of reinforced concrete rod elements

    Biodegradation Potential of SteccherinumOchraceum: Growth on Different Wood Types and Preliminary Evaluation of Enzymatic Activities

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    White-rot fungi isa source of a great variety of oxidative and hydrolytic enzymes suitable for biotechnological applications, e.g. in pulp and paper, textile and food industries, bioethanol production, degradation of recalcitrant environmental pollutants,and others. Steccherinumochraceum is a xylotrophicwhite-rot basidiomycetethat can be found in variousclimatic zones on different woody substrates (mostly well decayed). For this research, seventeenstrains of S. ochraceumwere collected in different regions of Russia from various wood substrates (aspen, alder, oak, hazel, birch and willow). Phylogeneticanalyseswere performedbasedon the nucleotide sequences of ITS1, ITS2, 5.8S rRNA, 28S rRNA, β-tubulin and tef1.Oxidaseandcellulaseactivitieswereassessedbyplate-tests with ABTS and CMC. Forevaluation of biodegradation potential,solid state fermentation on alder and pine sawdust wasperformed. Weightanddensitylossaswellas the C:Nratioweremeasuredafter 90 days of cultivation.All S. ochraceum strains exhibited high oxidative activity towards ABTS, indicating secretion of oxidative enzymes (i.e. laccases and class II peroxidases). Cellulase activity was medium or low for most strains and in some strains – absent. Allstrainswereabletodegradealderandpinesawdust. There was no correlation between the enzymatic activity, biodegradation potential and geographic origin of S. ochraceum strains. However, S. ochraceum strains isolated from the same wood substrates exhibited similar characteristics in most cases. Strain LE-BIN 3398 was the most effective for degrading both alder and pine sawdust and could be regarded as a promising source of oxidative enzymes for biotechnology. Keywords: basidiomycetes, biodegradation, solid state fermentation, oxidase activity, Steccherinumochraceu

    N-acetyltransferase 2 (NAT2) Gene Polymorphisms and the Effectiveness of Infertility Treatment in Patients with Peritoneal Endometriosis

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    Today, infertility has become a global issue. WHO ranks it the fifth among the major diseases of those below 60 years, after alcoholism, depression, injuries and eyesight disorders. Numerous studies conducted on the problems of infertility in endometriosis still do not offer clear answers regarding the pathogenesis and mechanisms of this disease and its influences on fertility. According to the survey results, point mutations of the NAT2 gene (NAT2*5 and NAT2*6) have been identified in 75.6% of the patients with infertility problems and the peritoneal form of endometriosis, that create “slow” allelic variants, which exceed the average index in the population. The peculiarities of the NAT2 gene polymorphisms have been proven to be associated with the effectiveness of the infertility treatment of female patients with peritoneal endometriosis. In the group of non-pregnant patients, the presence of с.341Т>C, c.481C>T, c.590G>A and c.803A>G heterozygous point mutations are 73.2, 73.2, 5.4, and 62.5%, respectively. The significant difference in the comparison of the allelic polymorphism during the various stages of the endometriosis was not identified. At stage III-IV endometriosis the frequency of three and more point substitutions was significantly higher. NAT2 gene polymorphisms can find use as an additional criterion for predicting the effectiveness of the infertility treatment of patients with peritoneal endometriosis

    Domestication as Enskilment : Harnessing Reindeer in Arctic Siberia

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    Acknowledgements Funding for this project was provided by the Wenner-Gren Foundation (SFR1725) to R. Losey, the JPI HUMANOR project (ESRC ES/M011054/1) to D. Anderson, ERC GRETPOL to D. Arzyutov, and the Russian Foundation for Basic Research to N.Fedorova (18-09-40011). The authors wish to express their gratitude to the Nenets families, the Okotettos and Yaungads, who hosted us during our stay in Iamal, which is greatly appreciated. Special thanks are also offered to the staff of Iamal-Nenets Autonomous District, and the staff of the Iamal-Nenets Regional Museum and Exhibition Complex of I.S. Shemanovskii, Peter the Great Museum of Anthropology and Ethnography, and British Museum for providing access to their collections.Peer reviewedPostprin

    Risk of hospitalization and death following prostate biopsy in Scotland

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    AbstractObjectiveTo investigate the risk of hospitalization and death following prostate biopsy.Study designRetrospective cohort study.MethodsOur study population comprised 10,285 patients with a record of first ever prostate biopsy between 2009 and 2013 on computerized acute hospital discharge or outpatient records covering Scotland. Using the general population as a comparison group, expected numbers of admissions/deaths were derived by applying age-, sex-, deprivation category-, and calendar year-specific rates of hospital admissions/deaths to the study population. Indirectly standardized hospital admission ratios (SHRs) and mortality ratios (SMRs) were calculated by dividing the observed numbers of admissions/deaths by expected numbers.ResultsCompared with background rates, patients were more likely to be admitted to hospital within 30 days (SHR 2.7; 95% confidence interval 2.4, 2.9) and 120 days (SHR 4.0; 3.8, 4.1) of biopsy. Patients with prior co-morbidity had higher SHRs. The risk of death within 30 days of biopsy was not increased significantly (SMR 1.6; 0.9, 2.7), but within 120 days, the risk of death was significantly higher than expected (SMR 1.9; 1.5, 2.4). The risk of death increased with age and tended to be higher among patients with prior co-morbidity. Overall risks of hospitalization and of death up to 120 days were increased both in men diagnosed and those not diagnosed with prostate cancer.ConclusionsHigher rates of adverse events in older patients and patients with prior co-morbidity emphasizes the need for careful patient selection for prostate biopsy and justifies ongoing efforts to minimize the risk of complications

    Genome-wide association studies targeting the yield of extraembryonic fluid and production traits in Russian White chickens

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    Background: The Russian White is a gene pool breed, registered in 1953 after crossing White Leghorns with local populations and, for 50 years, selected for cold tolerance and high egg production (EL). The breed has great potential in meeting demands of local food producers, commercial farmers and biotechnology sector of specific pathogen-free (SPF) eggs, the former valuing the breed for its egg weight (EW), EL, age at first egg (AFE), body weight (BW), and the latter for its yield of extraembryonic fluid (YEF) in 12.5-day embryos, ratio of extraembryonic fluid to egg weight, and embryo mass. Moreover, its cold tolerance has been presumably associated with day-old chick down colour (DOCDC) white rather than yellow, the genetic basis of these traits being however poorly understood. Results: We undertook genome-wide association studies (GWASs) for eight performance traits using single nucleotide polymorphism (SNP) genotyping of 146 birds and an Illumina 60KBeadChip. Several suggestive associations (p <5.16*10(-5)) were found for YEF, AFE, BW and EW. Moreover, on chromosome 2, an association with the white DOCDC was found where there is an linkage disequilibrium block of SNPs including genes that are responsible not for colour, but for immune resistance. Conclusions: The obtained GWAS data can be used to explore the genetics of immunity and carry out selection for increasing YEF for SPF eggs production.Peer reviewe
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