Control of spiral waves and turbulent states in a cardiac model by travelling-wave perturbations

We propose a travelling-wave perturbation method to control the spatiotemporal dynamics in a cardiac model. It is numerically demonstrated that the method can successfully suppress the wave instability (alternans in action potential duration) in the one-dimensional case and convert spiral waves and turbulent states to the normal travelling wave states in the two-dimensional case. An experimental scheme is suggested which may provide a new design for a cardiac defibrillator.Comment: 9 pages, 5 figure

catena-Poly[[chloridocopper(I)]-μ-η2,σ1-3-(2-allyl-2H-tetra­zol-5-yl)pyridine]

The title compound, [CuCl(C9H9N5)]n, prepared by solvo­thermal synthesis, is a new homometallic CuI–olefin coordination polymer in which the CuI atoms are linked by the 3-(2-allyl-2H-tetra­zol-5-yl)pyridine ligands and are each bonded to one terminal Cl atom. The organic ligand acts as a bidentate ligand bridging two neighboring Cu centers through the bonds to the N atom of the pyridine ring and the double bond of the allyl group. Weak Cu⋯Cl [3.136 (8) Å), C—H⋯Cl and C—H⋯N inter­actions connect the coordination polymers into a three-dimensional structure

catena-Poly[[di-μ-chlorido-dicopper(I)]bis­[μ-η2,σ1-4-(2-allyl-2H-tetra­zol-5-yl)pyridine]]

The title polymer, [Cu2Cl2(C9H9N5)2]n, has been prepared by the solvothermal treatment of CuCl with 4-(2-allyl-2H-tetra­zol-5-yl)pyridine. The crystal structure shows that the title compound is a homometallic CuI–olefin coordination polymer, in which the Cu2Cl2 nodes are bridged by two olefin ligands. The asymmetric unit contains one-half of the monomer, the complete monomer having twofold rotation symmetry. The coordination environment of CuI is slightly distorted tetra­hedral, with coordination sites being two μ2-Cl atoms, one pyridine N atom of an organic ligand and one allylic double bond of a symmetry-related ligand. Each organic mol­ecule behaves as a bidentate ligand, connecting two neighboring Cu2Cl2 dimers in the polymeric chain, which runs along [010]

Weak Decays of Doubly Heavy Baryons: Multi-body Decay Channels

The newly-discovered $\Xi_{cc}^{++}$ decays into the $\Lambda_{c}^+ K^-\pi^+\pi^+$, but the experimental data has indicated that this decay is not saturated by any two-body intermediate state. In this work, we analyze the multi-body weak decays of doubly heavy baryons $\Xi_{cc}$, $\Omega_{cc}$, $\Xi_{bc}$, $\Omega_{bc}$, $\Xi_{bb}$ and $\Omega_{bb}$, in particular the three-body nonleptonic decays and four-body semileptonic decays. We classify various decay modes according to the quark-level transitions and present an estimate of the typical branching fractions for a few golden decay channels. Decay amplitudes are then parametrized in terms of a few SU(3) irreducible amplitudes. With these amplitudes, we find a number of relations for decay widths, which can be examined in future.Comment: 47pages, 1figure. arXiv admin note: substantial text overlap with arXiv:1707.0657

Exact Single-Source SimRank Computation on Large Graphs

SimRank is a popular measurement for evaluating the node-to-node similarities based on the graph topology. In recent years, single-source and top-$k$ SimRank queries have received increasing attention due to their applications in web mining, social network analysis, and spam detection. However, a fundamental obstacle in studying SimRank has been the lack of ground truths. The only exact algorithm, Power Method, is computationally infeasible on graphs with more than $10^6$ nodes. Consequently, no existing work has evaluated the actual trade-offs between query time and accuracy on large real-world graphs. In this paper, we present ExactSim, the first algorithm that computes the exact single-source and top-$k$ SimRank results on large graphs. With high probability, this algorithm produces ground truths with a rigorous theoretical guarantee. We conduct extensive experiments on real-world datasets to demonstrate the efficiency of ExactSim. The results show that ExactSim provides the ground truth for any single-source SimRank query with a precision up to 7 decimal places within a reasonable query time.Comment: ACM SIGMOD 202

catena-Poly[[bromidocopper(I)]-μ-η2,σ1-3-(2-allyl-2H-tetra­zol-5-yl)pyridine]

The title compound, [CuBr(C9H9N5)]n, has been prepared by the solvothermal treatment of CuBr with 3-(2-allyl-2H-tetra­zol-5-yl)pyridine. It is a new homometallic CuI olefin coord­ination polymer in which the CuI atoms are linked by the 3-(2-allyl-2H-tetra­zol-5-yl)pyridine ligands and bonded to one terminal Br atom each. The organic ligand acts as a bidentate ligand connecting two neighboring Cu centers through the N atom of the pyridine ring and the double bond of the allyl group. A three-dimensional structure is formed through weak Cu—Br [3.1579 (8) Å], C—H⋯Br and C—H⋯N inter­actions