43 research outputs found

    Toward transient finite element simulation of thermal deformation of machine tools in real-time

    Get PDF
    Finite element models without simplifying assumptions can accurately describe the spatial and temporal distribution of heat in machine tools as well as the resulting deformation. In principle, this allows to correct for displacements of the Tool Centre Point and enables high precision manufacturing. However, the computational cost of FE models and restriction to generic algorithms in commercial tools like ANSYS prevents their operational use since simulations have to run faster than real-time. For the case where heat diffusion is slow compared to machine movement, we introduce a tailored implicit–explicit multi-rate time stepping method of higher order based on spectral deferred corrections. Using the open-source FEM library DUNE, we show that fully coupled simulations of the temperature field are possible in real-time for a machine consisting of a stock sliding up and down on rails attached to a stand

    Functional roles of fibroblast growth factor receptors (FGFRs) signaling in human cancers

    Full text link

    Germline selection shapes human mitochondrial DNA diversity.

    Get PDF
    Approximately 2.4% of the human mitochondrial DNA (mtDNA) genome exhibits common homoplasmic genetic variation. We analyzed 12,975 whole-genome sequences to show that 45.1% of individuals from 1526 mother-offspring pairs harbor a mixed population of mtDNA (heteroplasmy), but the propensity for maternal transmission differs across the mitochondrial genome. Over one generation, we observed selection both for and against variants in specific genomic regions; known variants were more likely to be transmitted than previously unknown variants. However, new heteroplasmies were more likely to match the nuclear genetic ancestry as opposed to the ancestry of the mitochondrial genome on which the mutations occurred, validating our findings in 40,325 individuals. Thus, human mtDNA at the population level is shaped by selective forces within the female germ line under nuclear genetic control, which ensures consistency between the two independent genetic lineages.NIHR, Wellcome Trust, MRC, Genomics Englan

    Suppression and azimuthal anisotropy of prompt and nonprompt J/psi production in PbPb collisions at root S-NN=2.76 TeV

    Get PDF
    The nuclear modification factor RAA and the azimuthal anisotropy coefficient v2 of prompt and nonprompt (i.e. those from decays of b hadrons) J/ψ mesons, measured from PbPb and pp collisions at sNN−−−√=2.76 TeV at the LHC, are reported. The results are presented in several event centrality intervals and several kinematic regions, for transverse momenta pT>6.5 GeV/c and rapidity |y|<2.4 , extending down to pT=3 GeV/c in the 1.6<|y|<2.4 range. The v2 of prompt J/ψ is found to be nonzero, but with no strong dependence on centrality, rapidity, or pT over the full kinematic range studied. The measured v2 of nonprompt J/ψ is consistent with zero. The RAA of prompt J/ψ exhibits a suppression that increases from peripheral to central collisions but does not vary strongly as a function of either y or pT in the fiducial range. The nonprompt J/ψ RAA shows a suppression which becomes stronger as rapidity or pT increases. The v2 and RAA of open and hidden charm, and of open charm and beauty, are compared

    Search for supersymmetry in the multijet and missing transverse momentum final state in pp collisions at 13 TeV

    Get PDF
    Peer reviewe

    Naso-ethmoid schwannoma with intracranial extension: case report Schwannoma naso-etmoidal com extensão intracraniana: relato de caso

    No full text
    Intranasal schwannomas are rare lesions, specially when they present with an intracranial extension. The fifth case in the medical literature of a naso-ethmoid schwannoma with extension into the anterior cranial fossa is presented. The magnetic resonance findings and the details of the combined intracranial / transfacial operative approach used are described. The possible origin and the clinical characteristics of this rare lesion are reviewed.<br>Schwannomas intranasais são lesões raras, principalmente quando apresentam um extensão intracraniana. Estamos apresentando o quinto caso da literatura médica de um schwannoma naso-etmoidal com extensão para o interior da fossa craniana anterior. São descritos os achados da ressonância magnética e os detalhes da via de acesso cirúrgico combinada intracraniana/transfacial. A possível origem e as características clínicas dessa lesaõ rara são revistas
    corecore