479 research outputs found
ALTERATION OF ACTIVE SUBSTANCE CONTENT IN "HEXACHLORAN DUST" PESTICIDE FORMULATION AT EXPOSURE TO ELECTRON BEAM
The most popular methods of organochlorinated pesticides (OCP) destruction, which are based on thermal dechlorination, are not ecologically safe. The other process – radiation-chemical degradation – has got some advantages. It does not involve high temperatures and expensive reagents. In this study, the effective OCP degradation was observed under irradiation of residuals of the active substance of ‘Hexachloran dust’ pesticide formulation, intended for utilization. Parameters for the preparation powder (dry form) exposure to electron beam are discussed. It is shown that at the exposure to electron beam at dose of 100 kGy, the degradation degree of hexachlorocyclohexane (HCH) isomers in a composition of active substance achieves 56.2–66.3%
Structuring ampelographic collections by phenotypic characteristics and comparing the reaction of grape varieties to climate change
Modern climate changes task breeders to adapt viticulture to the new natural resource potential of the regions. A necessary condition is the assessment and analysis of current trends in changing the characteristics of contrasting groups of varieties. The aim of the study is to identify homogeneous groups of varieties of an ampelographic collection and to compare the rates of reaction of their agrobiological parameters to climate changes. Material for the study consists of observations of 21 agrobiological characteristics of 109 grape varieties from the Don ampelographic collection named after Ya.I. Potapenko (Novocherkassk) with an observation period from 10 to 36 years in 1981–2017. The sample included Vitis vinifera L. varieties and the V. vinifera L. × V. labrusca L. and V. vinifera L. × V. amurensis Rupr. interspecific hybrids, and hybrids from crosses between V. vinifera L. and several American species. Homogeneous groups of characteristics and varieties are identified by principal component analysis (PCA) and analysis of variance (ANOVA) methods. Trends in changing the agrobiological characteristics of the varieties and groups of varieties are calculated. PCA revealed that the main differentiating factor of the studied fragment of the ampelographic collection is the size of the bunch; the second, the yield; the third, the time of ripening. The values of the factors are contrasting in varieties of different directions of use and taxonomic origin, which was confirmed by ANOVA. The groups of the V. vinifera × V. labrusca and V. vinifera × V. amurensis hybrids do not differ significantly from each other in most indicators, exceeding V. vinifera varieties in the number of elements of productivity, winter hardiness and yield. Complex hybrids with American species have an intermediate position between these groups exceeding all groups in bunch weight. All groups of cultivars show trends towards a reduction in productive period, an increase in the mass of bunch and yield, sugar content and a decrease in acidity. The V. vinifera × V. labrusca hybrids are distinguished by the highest growth rate of the bunch mass caused by a reduction in the duration of active growth and a decrease in the percentage of fruit-bearing shoots. A higher reduction rate of the production period and a decrease in acidity were observed in later varieties. Regression analysis showed that the acceleration of the ripening of grapes is largely due to rising temperatures
Bryophyte Diversity of Calcareous Fens in the Bashkir Cis-Urals (Republic of Bashkortostan, the Southern Urals)
The bryophyte diversity of base-rich fens was studied in 16 calcareous mires of the Bashkir Cis-Urals (the Southern Ural region). Thirty-seven moss species and nine liverworts were recorded in treeless communities dominated by Schoenus ferrugineus, Molinia caerulea, small sedges and mosses. The annotated species list with precise locations is provided. Most of the surveyed mires are located in the northeastern part of the Bashkir Cis-Urals, that is, in the Mesyagutovo forest-steppe bordering with the western foothills of the Southern Ural Mountains. In the plain areas of the western part of the Bashkir Cis-Urals, calcareous mires are very rare and characterized by the low number of habitat specialists. Arctic-boreo-alpine species (Cinclidium stygium,Paludella squarrosa, Palustriella decipiens, Pseudocalliergon trifarium, etc.) make up approximately 30% of the total bryophyte diversity of the surveyed fens. In the study area, these species grow in small isolated populations at the southern limit of the species range. Currently, only half of the surveyed calcareous mires are located within protected areas. It is essential to improve the protection of these unique habitats inthe study area.
Keywords: calcareous mires, base-rich fens, bryophytes, the Southern Ural
Genesis of biomarker hydrocarbons in the environment and their role in assessing an oil pollution source
Oil spills are classified according to chemical types that reflect qualitative and quantitative changes in petroleum composition during biodegradation in soil. Possible trends in composition of biomarker petroleum hydrocarbons in polluted soil, as determined by natural and climatic conditions and by activation of soil microflora, were revealed. It was shown that the use of selective bioremediation methods could lead to a noticeable redistribution of the relative amount of C27 : C28 : C29 steranes in marine crude oils owing to more intense degradation of C 27 steranes (5α, 14β, 17β, 20R and 20S, as well as 5α, 14α, 17α, 20R and 20S) as compared with their higher C29 homologues. The observed changes in the composition of steranes suggest another, namely, terrigenous origin of petroleum, and, thus, may lead to an erroneous conclusion concerning the genotype of crude oil as a pollution source. It was found that hopane hydrocarbons are highly stable under similar conditions. It was shown that the set of biomarker hydrocarbons might be useful as biological indicators in the assessment of a petroleum pollution source. © MAIK "Nauka/Interperiodica"
DNA marker identification of downy mildew resistance locus <i>Rpv10</i> in grapevine genotypes
One of the most common and harmful diseases of grapevine is downy mildew, caused by Plasmopara viticola. Cultivars of Vitis vinifera, the basis of high-quality viticulture, are mainly not resistant to downy mildew. Varieties with natural resistance to downy mildew belong to the vine species of North America and Asia (V. aestivalis, V. berlandieri, V. cinerea, V. labrusca, V. amurensis, etc.), as well as Muscadinia rotundifolia. The breeding of resistant cultivars is based on interspecific crossing. Currently, molecular genetic methods are increasingly used in pre-selection work and directly in breeding. One of the major loci of downy mildew resistance, Rpv10, was first identified in the variety Solaris and was originally inherited from wild V. amurensis. DNA markers that allow detecting Rpv10 in grapevine genotypes are known. We used PCR analysis to search for donors of resistance locus among 30 grape cultivars that, according to their pedigrees, could carry Rpv10. The work was performed using an automatic genetic analyzer, which allows obtaining high-precision data. Rpv10 locus allele, which determines resistance to the downy mildew pathogen, has been detected in 10 genotypes. Fingerprinting of grape cultivars with detected Rpv10 was performed at 6 reference SSR loci. DNA marker analysis revealed the presence of a resistance allele in the cultivar Korinka russkaya, which, according to publicly available data, is the offspring of the cultivar Zarya Severa and cannot carry Rpv10. Using the microsatellite loci polymorphism analysis and the data from VIVC database, it was found that Korinka russkaya is the progeny of the cultivar Severnyi, which is the donor of the resistance locus Rpv10. The pedigree of the grapevine cultivar Korinka russkaya was also clarified
DNA-marker based identification of the RPV3 gene determining downy mildew resistance in grapevines
Downy mildew is one of the most common fungal diseases of the vine, caused by Plasmopara viticola. An effective way to control the spread of the pathogen is to cultivate resistant varieties. Cultivars of Vitis vinifera, being the basis of high-quality viticulture, practically do not possess genetic resistance to P. viticola, so screening for resistance donors is an important stage in breeding. One of the major resistance loci to downy mildew, the Rpv3 gene, was identified in the genotype of a complex interspecific hybrid of grapes Bianca. Later, it was found that this gene had seven haplotypes of resistance inherited from North American grape species, and that it was possible to identify the allelic status of the gene using DNA-markers UDV305, UDV737. However, only two haplotypes can be combined in one diploid form. To determine the Rpv3 gene in the grape gene pool we, using these markers, studied 35 different genotypes of grapevines, most of which are interspecies cultivars. Three varieties with known allelic status of the Rpv3 gene (Dunavski lazur, Noah, Seyve Villard 12-375) were included in the study as reference genotypes. The genotypes were studied through polymerase chain reaction with separation of amplification products by capillary electrophoresis in automatic genetic analyzer ABI Prism 3130. In the studied grape cultivars DNA marker analysis indentified the Rpv3 gene in sixteen genotypes of interspecific origin, including haplotype Rpv3299-279 found in twelve varieties, Rpv3321-312 – in three, and haplotype Rpv3null-271 – in one variety. Seyve Villard 12-375 turned out to be the donor of resistance gene in the most of the genotypes carrying Rpv3 in this study. The obtained data can be useful in selection of mildew resistant grape varieties and screening for hybridization pairs
Characterisation of native Dagestan grape cultivars using SSR-analysis and the main ampelographic features of the leaves
Local, ancient grape cultivars of different cultivation regions are important part of grapevine genetic resources. Dagestan is one of the oldest regions of viticulture in the Russian Federation. Some Dagestan aboriginal grape varieties are cultivated on an industrial scale, while others are found in single numbers. The study of the native gene pool is given special attention in all grapes producing countries of the world. Currently, the most informative method of plant genotypes analysis is the study at the DNA level. The main features of the leaves of grape varieties are a key ampelographical characteristic. We studied cultivars Agadai, Alyi terskyi, Bor kara, Buday shuli, Gok ala, Gok izyum, Mahbor cibil, Yai izyum beliy, Yai izyum rozovyi by using these approaches. DNA profiles of 9 local Dagestan grape cultivars were obtained on microsatellite loci VVMD5, VVMD7, VVMD27, VVS2, VrZAG62 and VrZAG79 using an automated genetic analyzer ABI Prism 3130. The SSR-markers are recommended as the main for Vitis vinifera L. genotyping. The cultivars analyzed have different sets of allele combination by the loci studied. Evaluation of the genetic similarity of cultivars according to the results of microsatellite analysis showed that the genotypes of Mahbоr cibil and Aliy terskiy are closer to the Western European gene pool of V. vinifera L. than any other native varieties in the sample studied. In addition, the grapevine cultivars studied were described for the main features of the formed leaves according to the method of the international organization of vine and wine. The similarity of cultivars Gok Ala and Agadai was shown by the results of analysis of the leaves characteristics and according to SSR-profiling
Principles of meiotic chromosome assembly revealed in S. cerevisiae
During meiotic prophase, chromosomes organise into a series of chromatin loops emanating from a proteinaceous axis, but the mechanisms of assembly remain unclear. Here we use Saccharomyces cerevisiae to explore how this elaborate three-dimensional chromosome organisation is linked to genomic sequence. As cells enter meiosis, we observe that strong cohesin-dependent grid-like Hi-C interaction patterns emerge, reminiscent of mammalian interphase organisation, but with distinct regulation. Meiotic patterns agree with simulations of loop extrusion with growth limited by barriers, in which a heterogeneous population of expanding loops develop along the chromosome. Importantly, CTCF, the factor that imposes similar features in mammalian interphase, is absent in S. cerevisiae, suggesting alternative mechanisms of barrier formation. While grid-like interactions emerge independently of meiotic chromosome synapsis, synapsis itself generates additional compaction that matures differentially according to telomere proximity and chromosome size. Collectively, our results elucidate fundamental principles of chromosome assembly and demonstrate the essential role of cohesin within this evolutionarily conserved process
Snowbirds and infection--new phenomena in pneumonia and influenza hospitalizations from winter migration of older adults: A spatiotemporal analysis
A new measurement of antineutrino oscillation with the full detector configuration at Daya Bay
We report a new measurement of electron antineutrino disappearance using the
fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight
antineutrino detectors were installed in the summer of 2012. Including the 404
days of data collected from October 2012 to November 2013 resulted in a total
exposure of 6.910 GW-ton-days, a 3.6 times increase over
our previous results. Improvements in energy calibration limited variations
between detectors to 0.2%. Removal of six Am-C radioactive
calibration sources reduced the background by a factor of two for the detectors
in the experimental hall furthest from the reactors. Direct prediction of the
antineutrino signal in the far detectors based on the measurements in the near
detectors explicitly minimized the dependence of the measurement on models of
reactor antineutrino emission. The uncertainties in our estimates of
and were halved as a result of these
improvements. Analysis of the relative antineutrino rates and energy spectra
between detectors gave and eV in the three-neutrino
framework.Comment: Updated to match final published versio
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