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DNA repair associated with DNA replication is important for the conservation of genomic sequence information, whereas reconstitution of chromatin after replication sustains epigenetic information. We have isolated and characterized mutations in the BRU1 gene of Arabidopsis that suggest a novel link between these underlying maintenance mechanisms. Bru1(More)
SU(VAR)3-9 like histone methyltransferases control heterochromatic domains in eukaryotes. In Arabidopsis, 10 SUVH genes encode SU(VAR)3-9 homologues where SUVH1, SUVH2 and SUVH4 (KRYPTONITE) represent distinct subgroups of SUVH genes. Loss of SUVH1 and SUVH4 causes weak reduction of heterochromatic histone H3K9 dimethylation, whereas in SUVH2 null plants(More)
Non-woven cellulose II fabrics were used as scaffolds for in vitro cartilage tissue engineering. The scaffolds were activated in a saturated Ca(OH)(2) solution and subsequently coated with a calcium phosphate layer precipitated from a supersaturated physiological solution. Chondrocyte cell response and cartilage development were investigated. The cell(More)
The SU(VAR)3-9 protein family was first identified in animals as heterochromatin-associated proteins and found to control establishment of heterochromatic chromatin domains by histone H3 lysine 9 methylation. In Arabidopsis ten SU(VAR)3-9 homologous SUVH genes are found where SUVH1, SUVH2 and SUVH4 represent different subgroups of genes. Also the SUVH1,(More)
We investigate the phenomenon of space-charge driven emittance growth in a three-dimensional mismatched anisotropic charged particle beam with relevance to high-intensity linear accelerators. The final emittance growth can be understood as a superposition of the contributions from the mismatch-induced halo formation and from the anisotropy-induced energy(More)
Energy exchange between the longitudinal and transverse degrees of freedom of nonequipartitioned bunched beams (non-neutral plasmas) is investigated by means of 3D simulation. It is found that collective instability may lead to energy transfer in the direction of equipartition, without full progression to it, in certain bounded regions of parameter space(More)
The longitudinal coupling impedance of a cylindrical beam pipe for arbitrary relativistic gamma(0) and mode frequency is obtained analytically for finite wall conductivity and finite wall thickness. Closed form expressions for the electromagnetic fields excited by a beam perturbation are derived analytically. General expressions for the resistive-wall(More)
Experimental data on emittance exchange by the space charge driven " Montague resonance " have been obtained at the CERN Proton Synchrotron in 2002-04 as a function of the working point. These data are used to advance the benchmarking of major simulation codes (ACCSIM, IMPACT, MICROMAP, ORBIT, SIMBAD, SIMPSONS, SYNERGIA) currently employed worldwide in the(More)
Space charge can lead to emittance and/or energy exchange known as "equipartitioning issue" in linacs, or space-charge coupling in high-current synchrotrons. It is described here as an internal resonance driven by the self-consistent space-charge potential of coherent eigenmodes. By a detailed comparison of analytical theory with 2D particle-in-cell(More)
We show that pronounced collective nonlinear behavior is present in a beam with linear coupling and space charge as described by the complete second order moment equations. The collective effects result in a shifted and broadened resonance condition as well as saturation effects in the emittance transfer. For slow stop-band crossing either the beam evolves(More)