305 research outputs found

    Layered switch architectures for high-capacity optical transport networks

    Get PDF
    Cataloged from PDF version of article.We propose and analyze layered switch architectures that possess high design flexibility, greatly reduced switch size, and high expandability. The improvement in loss and crosstalk due to the reduced switch size is also discussed. Theoretical models have been developed to compute the network blocking probability using these architectures. Low blocking probability and high network utilization are achieved because of the capability of communication between layers in adjacent switches. The results show that the proposed layered switch architectures are very attractive for high-capacity optical transport networks

    BRST Algebra Quantum Double and Quantization of the Proper Time Cotangent Bundle

    Full text link
    The quantum double for the quantized BRST superalgebra is studied. The corresponding R-matrix is explicitly constucted. The Hopf algebras of the double form an analytical variety with coordinates described by the canonical deformation parameters. This provides the possibility to construct the nontrivial quantization of the proper time supergroup cotangent bundle. The group-like classical limit for this quantization corresponds to the generic super Lie bialgebra of the double.Comment: 11 pages, LaTe

    D=3 N=6 superconformal symmetry of AdS_4 x CP^3 superstring

    Full text link
    Invariance of the AdS_4 x CP^3 superstring under D=3 N=6 superconformal symmetry is discussed in the sector described by the OSp(4|6)/(SO(1,3) x U(3)) supercoset sigma-model action presented in the conformal basis for the osp(4|6)/(so(1,3) x u(3)) Cartan forms. Transformation rules under D=3 N=6 superconformal symmetry for the (10|24)-dimensional 'reduced' AdS_4 x CP^3 superspace coordinates are obtained and used to derive corresponding world-sheet currents.Comment: LaTeX, 23 pages; v2: presentation refined, typos corrected, references adde

    String versus Einstein frame in an AdS/CFT induced quantum dilatonic brane-world universe

    Get PDF
    AdS/CFT induced quantum dilatonic brane-world where 4d boundary is flat or de Sitter (inflationary) or Anti-de Sitter brane is considered. The classical brane tension is fixed but boundary QFT produces the effective brane tension via the account of corresponding conformal anomaly induced effective action. This results in inducing of brane-worlds in accordance with AdS/CFT set-up as warped compactification. The explicit, independent construction of quantum induced dilatonic brane-worlds in two frames: string and Einstein one is done. It is demonstrated their complete equivalency for all quantum cosmological brane-worlds under discussion, including several examples of classical brane-world black holes. This is different from quantum corrected 4d dilatonic gravity where de Sitter solution exists in Einstein but not in Jordan (string) frame. The role of quantum corrections on massive graviton perturbations around Anti-de Sitter brane is briefly discussed.Comment: LaTeX file, 24 pages, minor changes to match with published versio

    Cmr1/WDR76 defines a nuclear genotoxic stress body linking genome integrity and protein quality control

    Get PDF
    DNA replication stress is a source of genomic instability. Here we identify ​changed mutation rate 1 (​Cmr1) as a factor involved in the response to DNA replication stress in Saccharomyces cerevisiae and show that ​Cmr1—together with ​Mrc1/​Claspin, ​Pph3, the chaperonin containing ​TCP1 (CCT) and 25 other proteins—define a novel intranuclear quality control compartment (INQ) that sequesters misfolded, ubiquitylated and sumoylated proteins in response to genotoxic stress. The diversity of proteins that localize to INQ indicates that other biological processes such as cell cycle progression, chromatin and mitotic spindle organization may also be regulated through INQ. Similar to ​Cmr1, its human orthologue ​WDR76 responds to proteasome inhibition and DNA damage by relocalizing to nuclear foci and physically associating with CCT, suggesting an evolutionarily conserved biological function. We propose that ​Cmr1/​WDR76 plays a role in the recovery from genotoxic stress through regulation of the turnover of sumoylated and phosphorylated proteins

    Superconductivity in multi-phase Mg-B-O compounds

    Get PDF
    Structures of MgB2-based materials manufactured under pressure (up to 2 GPa) by different methods having high superconducting performance and connectivity are multiphase and contain different Mg-B-O compounds. Some oxygen can be incorporated into MgB2 and boron into MgO structures, MgBx (X=4-20) inclusions contain practically no oxygen. Regulating manufacturing temperature, pressure, introducing additions one can influence oxygen and boron distribution in the materials and thus, affect the formation, amount and sizes of Mg-B-O and MgBx inclusions and changing type of pinning, pinning force and so affect critical current density jc. The boron concentration increase in initial Mg and B mixture allows obtaining sample containing 88.5 wt% of MgB12 with Tc of 37.4 K (estimated magnetically)

    Mating dynamics in a nematode with three sexes and its evolutionary implications

    Get PDF
    Nematodes have diverse reproductive strategies, which make them ideal subjects for comparative studies to address how mating systems evolve. Here we present the sex ratios and mating dynamics of the free-living nematode Rhabditis sp. SB347, in which males, females and hermaphrodites co-exist. The three sexes are produced by both selfing and outcrossing, and females tend to appear early in a mother’s progeny. Males prefer mating with females over hermaphrodites, which our results suggest is related to the female-specific production of the sex pheromones ascr#1 and ascr#9. We discuss the parallels between this system and that of parasitic nematodes that exhibit alternation between uniparental and biparental reproduction
    • …
    corecore