Molecular Maps in Cereals: Methodology and Progress

Cereals provide for our major food crops, and therefore have been a subject of detailed genetic and cytogenetic studies during major part of the last century. These studies led to the preparation of linkage maps, which were also assigned to individual chromosomes, thus leading to the construction of chromosome maps in all major cereals. In some cases, the availability of cytogenetic stocks (e.g. deletion stocks in bread wheat) also allowed construction of physical maps. In the past, a major limitation in the construction of genetic maps has been the non-availability of mutants for majority of individual genes, so that only handful of genes could be mapped. However, during 1980s, the availability of molecular markers and the high level of DNA polymorphism, which they detect, led to renewed emphasis on genetic and physica.......

Characterization of Hypertension Risk Factors at the Committee on Temporary Shelter

Introduction: The health of homeless populations is at risk due to a high prevalence of undiagnosed hypertension (HTN) and cardiovascular disease (CVD). The interaction of housing and socioeconomic status with the risk factors for HTN and CVD remains unclear. Prevention of HTN through a healthy diet, exercise, adequate sleep, and avoidance of tobacco has been well described, but financial limitations and competing priorities for shelter and food make blood pressure (BP) control difficult for this population. By characterizing the risk factors and awareness of hypertension within the homeless population at the Committee on Temporary Shelter Daystation (COTS) in Burlington, Vermont, we may be able to identify promising avenues for therapeutic intervention.https://scholarworks.uvm.edu/comphp_gallery/1226/thumbnail.jp

Single nucleotide polymorphisms in rye (Secale cereale L.): discovery, frequency, and applications for genome mapping and diversity studies

To elucidate the potential of single nucleotide polymorphism (SNP) markers in rye, a set of 48 barley EST (expressed sequence tag) primer pairs was employed to amplify from DNA prepared from five rye inbred lines. A total of 96 SNPs and 26 indels (insertion–deletions) were defined from the sequences of 14 of the resulting amplicons, giving an estimated frequency of 1 SNP per 58 bp and 1 indel per 214 bp in the rye transcriptome. A mean of 3.4 haplotypes per marker with a mean expected heterozygosity of 0.66 were observed. The nucleotide diversity index (p) was estimated to be in the range 0.0059–0.0530. To improve assay cost-effectiveness, 12 of the 14 SNPs were converted to a cleaved amplified polymorphic sequence (CAPS) format. The resulting 12 SNP loci mapped to chromosomes 1R, 3R, 4R, 5R, 6R, and 7R, at locations consistent with their known map positions in barley. SNP genotypic data were compared with genomic simple sequence repeat (SSR) and EST-derived SSR genotypic data collected from the same templates. This showed a broad equivalence with respect to genetic diversity between these different data types

Radiation monitoring using imaging plate technology: A case study of leaves affected by the Chernobyl nuclear power plant and JCO criticality accidents

This paper describes the use of a photostimulable phosphor screen imaging technique to detect radioactive contamination in the leaves of wormwood (Artemisia vulgaris L) and fern (Dryopteris filix-max CL. Schoff) plants affected by the Chernobyl nuclear power plant accident. The imaging plate technology is well known for many striking performances in two-dimensional radiation detection. Since imaging plate comprises an integrated detection system, it has been extensively applied to surface contamination distribution studies. In this study, plant samples were collected from high- and low-contaminated areas of Ukraine and Belarus, which were affected due to the Chernobyl accident and exposed to imaging technique. Samples from the highly contaminated areas revealed the highest photo-stimulated luminescence on the imaging plate. Moreover, the radio nuclides detected in the leaves by gamma and beta ray spectroscopy were 137Cs and 90Sr, respectively. Additionally, in order to assess contamination, a comparison was also made with leaves of plants affected during the JCO criticality accident in Japan. Based on the results obtained, the importance of imaging plate technology in environmental radiation monitoring has been suggested

ПОВЫШЕНИЕ ЭФФЕКТИВНОСТИ ИСПОЛЬЗОВАНИЯ МОНОКРИСТАЛЛИЧЕСКОГО КРЕМНИЯ ПРИ РЕЗКЕ СЛИТКОВ НА ПЛАСТИНЫ

The paper presents a comparative analysis pertaining to cutting mono-crystal silicon by a diamond wheel with internal cutting-edge (DWIC) and a multi-stranded tool. It has been shown that in accordance to the output percentage of good plates usage of multi-stranded cutting method is on a par with DWIC; and in accordance to an actual consumption of silicon per one plate the first method exceeds the wheel cutting method. The process of multi-stranded cutting method is characterized by high accuracy, reproducibility, productivity and ensures significant saving of high-priced mono-crystal silicon.Представлены сравнительные результаты использования резки монокристаллического кремния алмазным кругом с внутренней режущей кромкой (АКВР) и  многопроволочной резки. Показано, что по проценту выхода годных пластин использование метода многопроволочной резки не уступает методу резки кругами АКВР, а по фактическому расходу кремния на одну пластину превосходит метод дисковой резки. Процесс многопроволочной резки характеризуется высокой точностью, воспроизводимостью, производительностью и обеспечивает существенную экономию дорогостоящего монокристаллического кремния.

Abscisic Acid Flux Alterations Result in Differential Abscisic Acid Signaling Responses and Impact Assimilation Efficiency in Barley under Terminal Drought Stress

Abscisic acid (ABA) is a central player in plant responses to drought stress. How variable levels of ABAabscisic acid under short-term versus long-term drought stress impact assimilation and growth in crops is unclear. We addressed this through comparative analysis, using two elite breeding lines of barley (Hordeum vulgare) that show senescence or stay-green phenotype under terminal drought stress and by making use of transgenic barley lines that express Arabidopsis (Arabidopsis thaliana) 9-cis-epoxycarotenoid dioxygenase (AtNCED6) coding sequence or an RNA interference (RNAi) sequence of ABA 8′-hydroxylase under the control of a drought-inducible barley promoter. The high levels of ABA and its catabolites in the senescing breeding line under long-term stress were detrimental for assimilate productivity, whereas these levels were not perturbed in the stay-green type that performed better. In transgenic barley, drought-inducible AtNCED expression afforded temporal control in ABA levels such that the ABA levels rose sooner than in wild-type plants but also subsided, unlike as in the wild type , to near-basal levels upon prolonged stress treatment due to down-regulation of endogenous HvNCED genes. Suppressing of ABA catabolism with the RNA interference approach of ABA 8′-hydroxylase caused ABA flux during the entire period of stress. These transgenic plants performed better than the wild type under stress to maintain a favorable instantaneous water use efficiency and better assimilation. Gene expression analysis, protein structural modeling, and protein-protein interaction analyses of the members of the PYRABACTIN RESISTANCE1/PYRABACTIN RESISTANCE1-LIKE/REGULATORY COMPONENT OF ABA RECEPTORS, TYPE 2C PROTEIN PHOSPHATASE Sucrose non-fermenting1-related protein kinase2, and ABA-INSENSITIVE5/ABA-responsive element binding factor family identified specific members that could potentially impact ABA metabolism and stress adaptation in barley

ФИЗИКО-ХИМИЧЕСКИЕ СВОЙСТВА УЛЬТРАДИСПЕРСНЫХ ПОРОШКОВ КРЕМНИЯ

Experimental investigations of ultradispersed silicon powder produced by mechanical grinding are conducted. The process of scaling powders using mechanochemical grinding was studied. It was found that the dimension of crystallites of the silicon powder determines their physical and chemical properties. Finely divided powders of silicon with a particle size ≤10 nm easily decompose water at room temperature into hydrogen and oxygen, they are easily oxidized by air oxygen and actively interact with hydroxides and acids with the release of significant amount of heat. The rate of saturation of micro- and ultradispersed powders with hydrogen at a constant rate of flow in the flow system depends on the temperature of the hydrogen hydrogenation process. It was found that the hydride formed at a low temperature (≤573 K) is in an equilibrium state when it is being hydrogenated in a flow reactor. The treated powder passes into a metastable state with the termination of the thermal action after hydrogenation. Hydrogen, entering the volume of micro- and ultradispersed silicon powder in the temperature range 373–723 K due to the diffusion process, can react not only with silicon atoms to form hydrides of the SiH2 type, but also with hydrides of less active radicals of the type of Si2H4, Si2H6. The hydrogenation process has two distinct stages. It is shown that the temperature of the transition between the stages is determined by the dispersion of micro- and ultradispersed silicon powders and by the structure of hydrides on the particle surface. As a result, it is established that the optimum temperature of hydrogenation should be taken at a temperature of 623 K, at which the maximum mobility of silicon atoms is reached during the formation of hydride. Sharp decrease in the hydrogen content is observed at a temperature above 723 K for the Si2H4 (SiH2).Проведены экспериментальные исследования ультрадисперсного порошка кремния, полученного путем помола полупроводникового монокристаллического кремния, изучен процесс масштабирования порошков с использованием механохимического измельчения. Установлено, что размерность кристаллитов порошков кремния определяет их физико-химические свойства. Ультрадисперсные порошки кремния с размером частиц ≤10 нм легко разлагают воду при комнатной температуре на водород и кислород, они легко окисляются кислородом воздуха и активно взаимодействуют с гидрооксидами и кислотами с выделением значительного количества тепла. Скорость насыщения микро- и ультрадисперсных порошков водородом при постоянной скорости потока в проточной системе зависит от температуры процесса гидрирования водорода. Установлено, что гидрид, образующийся при низкой температуре (≤573 К) находится в равновесном состоянии при гидрировании в проточном реакторе. С прекращением термического воздействия после гидрирования обработанный порошок переходит в метастабильное состояние. Водород, поступающий в объем микро- и ультрадисперсного порошка кремния в диапазоне температур 373–723 К за счет диффузионного процесса, может реагировать не только с атомами кремния с образованием гидридов типа SiH2, но и с гидридами менее активных радикалов типа Si2H4, Si2H6. Процесс гидрирования имеет две явно выраженные стадии. Показано, что температура перехода между стадиями определяется дисперсностью микро- и ультрадисперсных порошков кремния и структурой гидридов на поверхности частиц. В итоге установлено, что за оптимальную температуру гидрирования следует принять температуру 623 К, при которой достигается максимальная подвижность атомов кремния при формировании гидрида. При температуре выше 723 К для гидрида Si2H4 (SiH2) наблюдается резкое уменьшение содержания водорода

Spatial Structure of <i>Yersinia pestis</i> Population Belonging to Altai Biovar, Subspecies central asiatica Acording to Genome-Wide Sequencing Data

The aim of the work was to conduct phylogenetic analysis of Y. pestis strains, biovar altaica ssp. central asiatica, isolated in Gorno-Altai high-mountain and Sailyugem natural plague foci on the territory of Russia and Mongolia in 1965–2020, by full-genome sequencing data.Materials and methods. To determine the population structure of the biovar altaica ssp. central asiatica, 34 whole genome sequences were used (including 20 Y. pestis strains of the biovar altaica, 18 of which were sequenced by us). To isolate DNA from the Y. pestis strains, a PureLink Genomic DNA Mini Kit (Invitrogen, USA) was applied. Sequencing of the nucleotide sequences of Y. pestis strains was carried out in Ion PGM system Lifetechnologies. The analysis and processing of the obtained data were performed with the help of Newblergs Assembler 2.6 and IonTorrent Suite software package, 3.4.2. The search for SNPs was performed using the Wombac 2.0 program. The Maximum Likelihood dendrogram was built in the PhyML 3.1. The dendrogram was visualized using the FigTree 1.4.3 software.Results and discussion. Based on the data of whole genome analysis, taking into account the 1871 revealed polymorphic nucleotides, the spatial structure of the biovar altaica ssp. central asiatica has been determined. It includes several phylogeographic branches: the Kurai-Tarkhatinskaya (cluster 0.PE4a-1) and the Ulandryk-Mongolian (0.PE4a-2), which is in agreement with the geographical regions of the isolation of strains forming these branches in the Altai Mountains. The Kurai-Tarkhatinskaya branch is further divided into the Kurai (sub-cluster 0.PE4a-1-1, formed by the strains of 2009–2018) and Tarkhatinskaya (subcluster 0.PE4a-1-2, formed by the strains of 2012–2020) sub-branches, while the Ulandryk-Mongolian branch of evolution is split into sub-branches represented by strains from the Ulandryk meso focus (sub-cluster 0.PE4a-2-2, strains 1965–2010) and the Sailyugem focus of Mongolia (sub-cluster 0.PE4a-2-1, strains 1964–1990)