483 research outputs found

    Cold- and light-induced changes in the transcriptome of wheat leading to phase transition from vegetative to reproductive growth

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    <p>Abstract</p> <p>Background</p> <p>For plants to flower at the appropriate time, they must be able to perceive and respond to various internal and external cues. Wheat is generally a long-day plant that will go through phase transition from vegetative to floral growth as days are lengthening in spring and early summer. In addition to this response to day-length, wheat cultivars may be classified as either winter or spring varieties depending on whether they require to be exposed to an extended period of cold in order to become competent to flower. Using a growth regime to mimic the conditions that occur during a typical winter in Britain, and a microarray approach to determine changes in gene expression over time, we have surveyed the genes of the major pathways involved in floral transition. We have paid particular attention to wheat orthologues and functional equivalents of genes involved in the phase transition in <it>Arabidopsis</it>. We also surveyed all the MADS-box genes that could be identified as such on the Affymetrix genechip wheat genome array.</p> <p>Results</p> <p>We observed novel responses of several genes thought to be of major importance in vernalisation-induced phase transition, and identified several MADS-box genes that might play an important role in the onset of flowering. In addition, we saw responses in genes of the Gibberellin pathway that would indicate that this pathway also has some role to play in phase transition.</p> <p>Conclusion</p> <p>Phase transition in wheat is more complex than previously reported, and there is evidence that day-length has an influence on genes that were once thought to respond exclusively to an extended period of cold.</p

    Genetic studies on Trebbiano and morphologically related varieties by SSR and AFLP markers

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    Several grapevine varieties are named Trebbiano and have similar phenotypical characteristics (e.g. whitish berries, late ripening, vigorous growth). Other vines share many of the morphological characteristics of Trebbiano but have different names. In order to clarify the relationships between some of these varieties, a study was carried out with 7 Trebbiano varieties and 17 cultivars that are morphologically similar to Trebbiano. AFLP and SSR analyses were performed to define genetic similarity among the Trebbiano cultivars as well as between the Trebbiano cultivars and related varieties. Results show a large degree of variability between most of the cultivars and suggest that they do not share a common ancestor. Genetic analysis revealed that cv. Verdicchio is identical with Trebbiano di Soave which is very similar to Trebbiano di Lugana.

    Investigation of Dense Cesium Laser Plasma

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    A dense Cs vapour is irradiated by a tunable dye laser with the maximum power of 500KW and the half width of 20ns, and ionization mechanisms of the laser induced Cs plasma are investigated. An initial electron is produced by laser absorptions of the Cs molecular. At the high Cs number density, enough number of the Cs (6P) atoms are excited by electron collisions. If the dye laser is tuned to the atomic transition of 6P-9S, the Cs (6P) excited atom absorbs the further laser photon and is ionized. At the low Cs density, two-photon inoization is a main ionization process

    Question Box

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    Question: Wood is opaque to light but is easily penetrated by X rays. The latter, however, are stopped by some kinds of clear glass. Does this not show that light and X rays are of different nature? Is it desirable to study the theory of evolution in connection with a high school course in Botany? If so, to what extent? What is the purpose of crop rotation

    Health Literacy and Computer-Assisted Instruction: Usability and Patient Preference

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    The authors investigated the feasibility of using computer-assisted instruction in patients of varying literacy levels by examining patients’ preferences for learning and their ability to use 2 computer-based educational programs. A total of 263 participants 50–74 years of age with varying health literacy levels interacted with 1 of 2 educational computer programs as part of a randomized trial of a colorectal cancer screening decision aid. A baseline and postprogram evaluation survey were completed. More than half (56%) of the participants had limited health literacy. Regardless of literacy level, doctors were the most commonly used source of medical information—used frequently by 85% of limited and adequate literacy patients. In multivariate logistic regression, only those with health insurance (OR = 2.35, p = .06) and computer use experience (OR = 0.39, p .03) predicted the ability to complete the programs without assistance compared with those without health insurance or prior computer use, respectively. Although patients with limited health literacy had less computer experience, the majority completed the programs without any assistance and stated that they learned more than they would have from a brochure. Future research should investigate ways that computer-assisted instruction can be incorporated in medical care to enhance patient understanding

    CerealsDB 3.0:Expansion of resources and data integration

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    BACKGROUND: The increase in human populations around the world has put pressure on resources, and as a consequence food security has become an important challenge for the 21st century. Wheat (Triticum aestivum) is one of the most important crops in human and livestock diets, and the development of wheat varieties that produce higher yields, combined with increased resistance to pests and resilience to changes in climate, has meant that wheat breeding has become an important focus of scientific research. In an attempt to facilitate these improvements in wheat, plant breeders have employed molecular tools to help them identify genes for important agronomic traits that can be bred into new varieties. Modern molecular techniques have ensured that the rapid and inexpensive characterisation of SNP markers and their validation with modern genotyping methods has produced a valuable resource that can be used in marker assisted selection. CerealsDB was created as a means of quickly disseminating this information to breeders and researchers around the globe. DESCRIPTION: CerealsDB version 3.0 is an online resource that contains a wide range of genomic datasets for wheat that will assist plant breeders and scientists to select the most appropriate markers for use in marker assisted selection. CerealsDB includes a database which currently contains in excess of a million putative varietal SNPs, of which several hundreds of thousands have been experimentally validated. In addition, CerealsDB also contains new data on functional SNPs predicted to have a major effect on protein function and we have constructed a web service to encourage data integration and high-throughput programmatic access. CONCLUSION: CerealsDB is an open access website that hosts information on SNPs that are considered useful for both plant breeders and research scientists. The recent inclusion of web services designed to federate genomic data resources allows the information on CerealsDB to be more fully integrated with the WheatIS network and other biological databases. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12859-016-1139-x) contains supplementary material, which is available to authorized users

    Helium Clustering in Neutron-Rich Be Isotopes

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    Measurements of the helium-cluster breakup and neutron removal cross sections for neutron-rich Be isotopes A=10-12,14 are presented. These have been studied in the 30 to 42 MeV/u energy range where reaction measurements are proposed to be sensitive to the cluster content of the ground-state wave-function. These measurements provide a comprehensive survey of the decay processes of the Be isotopes by which the valence neutrons are removed revealing the underlying alpha-alpha core-cluster structure. The measurements indicate that clustering in the Be isotopes remains important up to the drip-line nucleus 14^Be and that the dominant helium-cluster structure in the neutron-rich Be isotopes corresponds to alpha-Xn-alpha.Comment: 5 pages, 2 tables and 3 figure

    \b{eta}-delayed three-proton decay of 31Ar

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    The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880 MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a gaseous time projection chamber with optical readout allowing to record decay events with emission of protons. In addition to \b{eta}-delayed emission of one and two protons we have clearly observed the beta-delayed three-proton branch. The branching ratio for this channel in 31Ar is found to be 0.07(2)%.Comment: 5 pages, 3 figures, submitted to Physical Rev.

    Chemotaxis Based Virtual Fence for Swarm Robots in Unbounded Environments

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    This paper presents a novel swarm robotics application of chemotaxis behaviour observed in microorganisms. This approach was used to cause exploration robots to return to a work area around the swarm’s nest within a boundless environment. We investigate the performance of our algorithm through extensive simulation studies and hardware validation. Results show that the chemotaxis approach is effective for keeping the swarm close to both stationary and moving nests. Performance comparison of these results with the unrealistic case where a boundary wall was used to keep the swarm within a target search area showed that our chemotaxis approach produced competitive results
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