73 research outputs found
Metagenomics of bolidophyceae in plankton and ice of the White Sea
© 2017, Pleiades Publishing, Ltd. The molecular diversity of poorly studied algae of Bolidophyceae class was first estimated by Illumina sequencing of V4 region of 18S rRNA gene in ice, under-ice water and summer water of the subarctic White Sea. We used two clustering thresholds–93 and 97%–and revealed 31 phylotypes of Bolidophyceae. Triparma pacifica and Т. strigata were identified to species level. The association of individual phylotypes to certain biotopes (ice or plankton) and stages of seasonal succession (under ice or summer plankton) has been established. Some phylotypes are found in different biotopes and over a wide temperature range. Due to changing their genetic composition, Bolidophyceae are a constant component of the photoautotrophic plankton and ice communities
The mitochondrial genome of the moss Brachythecium rivulare (Hypnales, Brachytheciaceae)
© 2017, Pleiades Publishing, Ltd. The mitochondrial genome of the pleurocarpous moss Brachythecium rivulare has been sequenced and annotated. The genome consists of 104,460 base pairs and has approximately the same gene set and organization as other bryophyte mitogenomes. Whole mitochondrial genome comparison between B. rivulare and Physcomitrella patens, Tetraphis pellucida, Anomodon rugelii, and Anomodon attenuatus was performed. The primary cause of bryophyte mitochondrial gene length variation was found to be numerous indels in the introns. Bryophyte mitochondrial gene conservation level was estimated, and it was in a good congruence with the overall phylogeny of bryophytes with the percentage of mitogenome similarity being proportional to the age estimated by phylochronologic analysis. Annotation discrepancies in the analyzed mitogenome sequences were identified. The simple sequence repeat (SSR) content was evaluated, and candidate sites of RNA editing were predicted in the B. rivulare mitochondrial genome
ОТ МЕТАЛЛУРГИИ ГРАНУЛ К АДДИТИВНЫМ ТЕХНОЛОГИЯМ
OJSC «Kompozit» traces its history back to the Central Research Institute of Materials Science (CRIMS) and successfully acts as a leading material science institute in the rocket and space industry up to the present day. The enterprise uses and improves state-of-theart technologies, and creates a variety of new metal, non-metallic, composite and ceramic materials. This article provides an overview of powder sector development from the metallurgy of granules to additive technologies and shows the participation of MISIS graduates. The experience of OJSC «Kompozit» in the manufacturing of parts by selective electron beam melting (SEBM) of home-made VT6S titanium alloy powders. Initial powders are obtained by plasma centrifugal spraying of the bar stock. It is shown that the powders feature an ideal spherical shape, low defect rate, high processability and fully meet the process requirements. The microstructure and properties of samples and parts obtained by the SEBM are studied.ОАО «Композит» ведет свою историю от Центрального научно-исследовательского института материаловедения (ЦНИИМВ) и до сегодняшнего дня успешно выполняет функции головного материаловедческого института в ракетно-космической отрасли. На предприятии используются и совершенствуются самые передовые технологии, создаются различные новые металлические, неметаллические, композиционные и керамические материалы. В представленном обзоре показано развитие порошкового направления от металлургии гранул к аддитивным технологиям, в том числе с участием выпускников МИСиС. Рассмотрен опыт ОАО «Композит» в области изготовления деталей методом селективного электронно-лучевого сплавления (СЭЛС) порошков титанового сплава ВТ6С собственного производства. Исходные порошки получены методом плазменного центробежного распыления прутковой заготовки. Показано, что порошки характеризуются идеальной сферической формой, низким уровнем дефектности, высокими технологическими свойствами и полностью соответствуют требованиям процесса. Изучены микроструктура и свойства образцов и деталей, полученных методом СЭЛС
Non-Alcoholic Fatty Liver Disease in Cardiac Patients with Overweight and Obesity
Aim. In this research, we set out to study organic changes in the heart and blood vessels of obese men suffering from non-alcoholic fatty liver disease (NAFLD) combined with cardiac pathology in the metabolically unhealthy phenotype (MUHP). Another objective consisted in establishing a relationship between liver damage and the pathology of the heart and blood vessels.Materials and methods. A group of 112 men (male)aged 61.2±1.7 diagnosed with the ischemic heart disease (IHD) and stage 1–3 arterial hypertension (AH) were examined during the stationary treatment in the Republican Clinical Diagnostic Centre (Izhevsk, Russia). The patients were divided into 3 groups according to their body mass index (BMI): 29 men with a BMI under 25 kg/m2(I group); 43 overweight men a BMI over 25 of kg/m2(II group); 40 men with obesity and a BMI above 30 of kg/m2(III group). Laboratory and non-invasive instrumental examinations required for the diagnostics of NAFLD and IHD were carried out, including liver ultrasound and FibroScan elastometry. Other examinations included the measurement of the intra-abdominal adipose tissue (IAT) and epicardial adipose tissue (EAT) thickness, the calculation of the visceral adiposity index (VAI), the estimation of endothelial dysfunction indicators, as well as the assessment of the structural and functional parameters of the heart and blood vessels.Results. In obese patients with pronounced NAFLD signs, IAT, EAT and VAI indicators are shown to increase in direct correlation with the parameters of liver steatosis. A relationship is established between the most significant structural and functional indicators of the heart (myocardial mass index, volume of the left atrium), blood vessels (endotheliumdependent vasodilation, the size of the intima-media complex of the common carotid artery) and NAFLD. It is demonstrated that the correlation coefficients grow with the progression of fatty infiltration and liver fibrosis signs.Conclusions. The results of the study have revealeda connection between the NAFLD presence and the main markers of visceral fat depots (IAT, EAT, VAI), which is shown to increase the risk of cardio-vascular complications in such patients. NAFLD is accompanied by endothelial dysfunction and a change in the most significant parameters of cardiac and vascular remodelling. These parameters manifest the progression of pathological changes in the liver parenchyma, which increases the cardio-metabolic risk in patients with MUHP
High-quality genome assembly of Capsella bursa-pastoris reveals asymmetry of regulatory elements at early stages of polyploid genome evolution
© 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd Polyploidization and subsequent sub- and neofunctionalization of duplicated genes represent a major mechanism of plant genome evolution. Capsella bursa-pastoris, a widespread ruderal plant, is a recent allotetraploid and, thus, is an ideal model organism for studying early changes following polyploidization. We constructed a high-quality assembly of C. bursa-pastoris genome and a transcriptome atlas covering a broad sample of organs and developmental stages (available online at http://travadb.org/browse/Species=Cbp). We demonstrate that expression of homeologs is mostly symmetric between subgenomes, and identify a set of homeolog pairs with discordant expression. Comparison of promoters within such pairs revealed emerging asymmetry of regulatory elements. Among them there are multiple binding sites for transcription factors controlling the regulation of photosynthesis and plant development by light (PIF3, HY5) and cold stress response (CBF). These results suggest that polyploidization in C. bursa-pastoris enhanced its plasticity of response to light and temperature, and allowed substantial expansion of its distribution range
Sequencing and Analysis of Plastid Genome in Mycoheterotrophic Orchid Neottia nidus-avis
Plastids are the semiautonomous organelles that possess their own genome inherited from the cyanobacterial ancestor. The primary function of plastids is photosynthesis so the structure and evolution of plastid genomes are extensively studied in photosynthetic plants. In contrast, little is known about the plastomes of nonphotosynthetic species. In higher plants, plastid genome sequences are available for only three strictly nonphotosynthetic species, the liverwort Aneura mirabilis and two flowering plants, Epifagus virginiana and Rhizanthella gardneri. We report here the complete sequence of a plastid genome of nonphotosynthetic mycoheterotrophic orchid Neottia nidus-avis, determined using 454 pyrosequencing technology. It was found to be reduced in both genome size and gene content; this reduction is however not as drastic as in the other nonphotosynthetic orchid, R. gardneri. Neottia plastome lacks all genes encoding photosynthetic proteins, RNA polymerase subunits but retains most genes of translational apparatus. Those genes that are retained have an increased rate of both synonymous and nonsynonymous substitutions but do not exhibit relaxation of purifying selection either in Neottia or in Rhizanthella
ПОЛУЧЕНИЕ СУБМИКРОННЫХ ПОРОШКОВ И НАНОСТРУКТУРИРОВАННЫХ ГРАНУЛ НА ОСНОВЕ NiAl МЕТОДОМ СВС ИЗ МЕХАНИЧЕСКИ АКТИВИРОВАННОЙ СМЕСИ
The influence of parameters of mechanical activation (MA) on the structure and phase composition of the Ni–Al reaction mixtures as well as the products that are formed from them during the subsequent self-propagating high-temperature synthesis (SHS) is investigated using optical and electron microscopy, X-ray structural analysis, electron probe microanalysis, and laser diffraction. Optimal MA modes of reaction mixtures and optimal synthesis conditions of porous cakes are determined. Special functional additives of Al2O3, BN, and WC powders, which increase the cake porosity and facilitate the subsequent grinding, are selected; and their amount is determined. It is revealed that boron nitride and tungsten carbide additives most efficiently promote the destruction of NiAl particles. Submicron powders with the NiAl-based nanoblock structure are prepared.С использованием методов оптической и электронной микроскопии, рентгеноструктурного и рентгеноспектрального анализов, лазерной дифракции исследовано влияние параметров механического активирования (МА) на структуру и фазовый состав реакционных смесей Ni–Al, а также образующихся из них при последующем самораспространяющемся высокотемпературном синтезе (СВС) продуктов. Определены оптимальные режимы МА реакционных смесей и условиясинтеза пористых спеков. Выбраны специальные функциональные добавки нанопорошков Al2O3, BN и WC , которые увеличивают пористость спеков и облегчают последующее измельчение, и определено их количество. Выявлено, что наиболее эффективно способствуют разрушению частиц NiAl добавки нитрида бора и карбида вольфрама. Получены субмикронные порошки с наноблочной структурой на основе NiAl
Selection and Validation of Reference Genes for Quantitative Real-Time PCR in Buckwheat (Fagopyrum esculentum) Based on Transcriptome Sequence Data
Quantitative reverse transcription PCR (qRT-PCR) is one of the most precise and widely used methods of gene expression analysis. A necessary prerequisite of exact and reliable data is the accurate choice of reference genes. We studied the expression stability of potential reference genes in common buckwheat (Fagopyrum esculentum) in order to find the optimal reference for gene expression analysis in this economically important crop. Recently sequenced buckwheat floral transcriptome was used as source of sequence information. Expression stability of eight candidate reference genes was assessed in different plant structures (leaves and inflorescences at two stages of development and fruits). These genes are the orthologs of Arabidopsis genes identified as stable in a genome-wide survey gene of expression stability and a traditionally used housekeeping gene GAPDH. Three software applications – geNorm, NormFinder and BestKeeper - were used to estimate expression stability and provided congruent results. The orthologs of AT4G33380 (expressed protein of unknown function, Expressed1), AT2G28390 (SAND family protein, SAND) and AT5G46630 (clathrin adapter complex subunit family protein, CACS) are revealed as the most stable. We recommend using the combination of Expressed1, SAND and CACS for the normalization of gene expression data in studies on buckwheat using qRT-PCR. These genes are listed among five the most stably expressed in Arabidopsis that emphasizes utility of the studies on model plants as a framework for other species
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