| 1. |
- Acharya, B. S., et al.
(author)
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Introducing the CTA concept
- 2013
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In: Astroparticle physics. - : Elsevier BV. - 0927-6505 .- 1873-2852. ; 43, s. 3-18
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Journal article (other academic/artistic)abstract
- The Cherenkov Telescope Array (CTA) is a new observatory for very high-energy (VHE) gamma rays. CTA has ambitions science goals, for which it is necessary to achieve full-sky coverage, to improve the sensitivity by about an order of magnitude, to span about four decades of energy, from a few tens of GeV to above 100 TeV with enhanced angular and energy resolutions over existing VHE gamma-ray observatories. An international collaboration has formed with more than 1000 members from 27 countries in Europe, Asia, Africa and North and South America. In 2010 the CTA Consortium completed a Design Study and started a three-year Preparatory Phase which leads to production readiness of CTA in 2014. In this paper we introduce the science goals and the concept of CTA, and provide an overview of the project. (C) 2013 Elsevier B.V. All rights reserved.
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| 2. |
- Badreddine, Ilham, et al.
(author)
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Cell Wall Chitosaccharides Are Essential Components and Exposed Patterns of the Phytopathogenic Oomycete Aphanomyces euteiches
- 2008
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In: Eukaryotic Cell. - : American Society for Microbiology. - 1535-9778 .- 1535-9786. ; 7:11, s. 1980-1993
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Journal article (peer-reviewed)abstract
- Chitin is an essential component of fungal cell walls, where it forms a crystalline scaffold, and chitooligosaccharides derived from it are signaling molecules recognized by the hosts of pathogenic fungi. Oomycetes are cellulosic fungus-like microorganisms which most often lack chitin in their cell walls. Here we present the first study of the cell wall of the oomycete Aphanomyces euteiches, a major parasite of legume plants. Biochemical analyses demonstrated the presence of ca. 10% N-acetyl-D-glucosamine (GlcNAc) in the cell wall. Further characterization of the GlcNAc-containing material revealed that it corresponds to noncrystalline chitosaccharides associated with glucans, rather than to chitin per se. Two putative chitin synthase (CHS) genes were identified by data mining of an A. euteiches expressed sequence tag collection and Southern blot analysis, and full-length cDNA sequences of both genes were obtained. Phylogeny analysis indicated that oomycete CHS diversification occurred before the divergence of the major oomycete lineages. Remarkably, lectin labeling showed that the Aphanomyces euteiches chitosaccharides are exposed at the cell wall surface, and study of the effect of the CHS inhibitor nikkomycin Z demonstrated that they are involved in cell wall function. These data open new perspectives for the development of antioomycete drugs and further studies of the molecular mechanisms involved in the recognition of pathogenic oomycetes by the host plants.
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| 3. |
- Bécoulet, A., et al.
(author)
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Science and technology research and development in support to ITER and the Broader Approach at CEA
- 2013
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10
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Journal article (peer-reviewed)abstract
- In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, plasma performance, as well as mitigating the risks of the procurement phase. This overview reports the latest progress in both fusion science and technology including many areas, namely the mitigation of superconducting magnet quenches, disruption-generated runaway electrons, edge-localized modes (ELMs), the development of imaging surveillance, and heating and current drive systems for steady-state operation. The WEST (W Environment for Steady-state Tokamaks) project, turning Tore Supra into an actively cooled W-divertor platform open to the ITER partners and industries, is presented.
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| 4. |
- Dumas, Bernard, et al.
(author)
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How Long do Unilateral Target Zones Last?
- 1991
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Reports (other academic/artistic)abstract
- We examine the expected survival time of a unilateral exchange rate target zone, when constraints on monetary policy prevent the central bank from exclusively focusing on defending the target zone. Generally the width of the target zone has a negligible effect on the expected survival time, and the dominant determinants are reserve levels and the degree of real and monetary divergence between the country in question and the rest of the world. For seemingly realistic parameters, the expected survivial time is fairly long: a few decades rather than a few years.
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| 5. |
- Jiang, Rays H. Y., et al.
(author)
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Distinctive Expansion of Potential Virulence Genes in the Genome of the Oomycete Fish Pathogen Saprolegnia parasitica
- 2013
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In: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 9:6, s. e1003272-
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Journal article (peer-reviewed)abstract
- Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica.
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| 6. |
- Rabionet, Mariona, et al.
(author)
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Epidermal 1-O-acylceramides appear with the establishment of the water permeability barrier in mice and are produced by maturating keratinocytes
- 2022
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In: Lipids. - : Wiley. - 0024-4201 .- 1558-9307. ; 57:3, s. 183-195
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Journal article (peer-reviewed)abstract
- 1-O-Acylceramides (1-OACs) have a fatty acid esterified to the 1-hydroxyl of the sphingosine head group of the ceramide, and recently we identified these lipids as natural components of human and mouse epidermis. Here we show epidermal 1-OACs arise shortly before birth during the establishment of the water permeability barrier in mice. Fractionation of human epidermis indicates 1-OACs concentrate in the stratum corneum. During in vitro maturation into reconstructed human epidermis, human keratinocytes dramatically increase 1-OAC levels indicating they are one source of epidermal 1-OACs. In search of potential enzymes responsible for 1-OAC synthesis in vivo, we analyzed mutant mice with deficiencies of ceramide synthases (Cers2, Cers3, or Cers4), diacylglycerol acyltransferases (Dgat1 or Dgat2), elongase of very long fatty acids 3 (Elovl3), lecithin cholesterol acyltransferase (Lcat), stearoyl-CoA desaturase 1 (Scd1), or acidic ceramidase (Asah1). Overall levels of 1-OACs did not decrease in any mouse model. In Cers3 and Dgat2-deficient epidermis they even increased in correlation with deficient skin barrier function. Dagt2 deficiency reshapes 1-OAC synthesis with an increase in 1-OACs with N-linked non-hydroxylated fatty acids and a 60% decrease compared to control in levels of 1-OACs with N-linked hydroxylated palmitate. As none of the single enzyme deficiencies we examined resulted in a lack of 1-OACs, we conclude that either there is functional redundancy in forming 1-OAC and more than one enzyme is involved, and/or an unknown acyltransferase of the epidermis performs the final step of 1-OAC synthesis, the implications of which are discussed.
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