7 research outputs found

    Les effets des électrons chauds sur le calcul des taux d’ionisation du Be et des ions Be+1, Be+2 et Be+3

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    Pour un model collisionnel radiatif, les densités des populations des niveaux atomiques sont déterminées par un système d’équations contenant les taux des différents processus atomiques. L’ionisation par impact électronique est un processus atomique indispensable dans la simulation des émissions radiatives des raies et aussi pour l’étude du bilan ionique. Plusieurs problèmes liés à l’étude des plasmas de laboratoire, d’astrophysique et defusion thermonucléaire contrôlée nécessitent la connaissance au préalable de la structureatomique comme les énergies des différents niveaux et les sectionsefficaces. Dans notre travail, nous avons choisi le code FAC (Flexible Atomic Code) pour calculer les sections efficaces d’ionisation de l'atome de Be et les ionsBe+1, Be+2 et Be+3. Les taux d’ionisation seront générés par un calcul numérique. Nous avons étudié les effets de la fraction des électrons chauds sur le taux d’ionisation. La fraction des électrons chauds est représentée par une distribution non-Maxwellienne. Les taux d’ionisation sont générés à partir des sections efficaces et pondérées par cette distribution. L’utilisation d’une distribution Non-Maxwellienne des électrons chauds, pour différentes fractions nous a permis de montrer la sensibilité de ces taux par rapport aux fractions des électrons chauds. Les résultats sont comparés à ceux trouvés dans la littérature

    BloodChIP: A database of comparative genome-wide transcription factor binding profiles in human blood cells

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    The BloodChIP database (http://www.med.unsw.edu.au/CRCWeb.nsf/page/ BloodChIP) supports exploration and visualization of combinatorial transcription factor (TF) binding at a particular locus in human CD34-positive and other normal and leukaemic cells or retrieval of target gene sets for user-defined combinations of TFs across one or more cell types. Increasing numbers of genome-wide TF binding profiles are being added to public repositories, and this trend is likely to continue. For the power of these data sets to be fully harnessed by experimental scientists, there is a need for these data to be placed in context and easily accessible for downstream applications. To this end, we have built a user-friendly database that has at its core the genome-wide binding profiles of seven key haematopoietic TFs in human stem/progenitor cells. These binding profiles are compared with binding profiles in normal differentiated and leukaemic cells. We have integrated these TF binding profiles with chromatin marks and expression data in normal and leukaemic cell fractions. All queries can be exported into external sites to construct TF-gene and protein-protein networks and to evaluate the association of genes with cellular processes and tissue expression. © 2013 The Author(s). Published by Oxford University Press.published_or_final_versio

    Cancer-Associated noncoding mutations affect RNA G-quadruplex-mediated regulation of gene expression

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    © 2017 The Author(s). Cancer is a multifactorial disease driven by a combination of genetic and environmental factors. Many cancer driver mutations have been characterised in protein-coding regions of the genome. However, mutations in noncoding regions associated with cancer have been less investigated. G-quadruplex (G4) nucleic acids are four-stranded secondary structures formed in guanine-rich sequences and prevalent in the regulatory regions. In this study, we used published whole cancer genome sequence data to find mutations in cancer patients that overlap potential RNA G4-forming sequences in 5⠲ UTRs. Using RNAfold, we assessed the effect of these mutations on the thermodynamic stability of predicted RNA G4s in the context of full-length 5⠲ UTRs. Of the 217 identified mutations, we found that 33 are predicted to destabilise and 21 predicted to stabilise potential RNA G4s. We experimentally validated the effect of destabilising mutations in the 5⠲ UTRs of BCL2 and CXCL14 and one stabilising mutation in the 5⠲ UTR of TAOK2. These mutations resulted in an increase or a decrease in translation of these mRNAs, respectively. These findings suggest that mutations that modulate the G4 stability in the noncoding regions could act as cancer driver mutations, which present an opportunity for early cancer diagnosis using individual sequencing information.published_or_final_versio

    The SIB Swiss Institute of Bioinformatics' resources: focus on curated databases

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    The SIB Swiss Institute of Bioinformatics (www.isb-sib.ch) provides world-class bioinformatics databases, software tools, services and training to the international life science community in academia and industry. These solutions allow life scientists to turn the exponentially growing amount of data into knowledge. Here, we provide an overview of SIB's resources and competence areas, with a strong focus on curated databases and SIB's most popular and widely used resources. In particular, SIB's Bioinformatics resource portal ExPASy features over 150 resources, including UniProtKB/Swiss-Prot, ENZYME, PROSITE, neXtProt, STRING, UniCarbKB, SugarBindDB, SwissRegulon, EPD, arrayMap, Bgee, SWISS-MODEL Repository, OMA, OrthoDB and other databases, which are briefly described in this article

    The SIB Swiss Institute of bioinformatics\u27 resources: Focus on curated databases

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    \ua9 The Author(s) 2015.The SIB Swiss Institute of Bioinformatics (www. isb-sib.ch) provides world-class bioinformatics databases, software tools, services and training to the international life science community in academia and industry. These solutions allow life scientists to turn the exponentially growing amount of data into knowledge. Here, we provide an overview of SIB\u27s resources and competence areas, with a strong focus on curated databases and SIB\u27s most popular and widely used resources. In particular, SIB\u27s Bioinformatics resource portal ExPASy features over 150 resources, including UniProtKB/Swiss-Prot, ENZYME, PROSITE, neXtProt, STRING, UniCarbKB, SugarBindDB, SwissRegulon, EPD, arrayMap, Bgee, SWISS-MODEL Repository, OMA, OrthoDB and other databases, which are briefly described in this article

    Abstracts of 1st International Conference on Computational & Applied Physics

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    This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria
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