Short Cycle Covers of Cubic Graphs and Graphs with Minimum Degree Three

The Shortest Cycle Cover Conjecture of Alon and Tarsi asserts that the edges of every bridgeless graph with $m$ edges can be covered by cycles of total length at most $7m/5=1.400m$. We show that every cubic bridgeless graph has a cycle cover of total length at most $34m/21\approx 1.619m$ and every bridgeless graph with minimum degree three has a cycle cover of total length at most $44m/27\approx 1.630m$

Bis(2,2′-bipyridyl-κ2 N,N′)bis­(2-hydroxy­benzoato)-κO 1;κ2 O 1,O 1′-cadmium(II) methanol solvate

The title compound, [Cd(C7H5O3)2(C10H8N2)2]·CH3OH, contains one monomeric seven-coordinate cadmium complex and one methanol solvate mol­ecule. The CdII atom is coordinated to two 2,2′-bipyridyl ligands via the N atoms and to two salicylate anions (Hsal−) via the carboxyl­ate O atoms, which act as monodentate ligand for the one and bidentate ligand for the second. The CdII atom exhibits a {6 + 1} environment, approximately described as a distorted capped octa­hedron with the apical positions occupied by one of the two N atoms belonging to one bipyridyl ligand and one of the two carboxyl­ate O atoms from the monodentate Hsal− ligand. Two intra­molecular six-membered hydrogen-bonded rings are present, generated from inter­actions between the carboxyl­ate and hydr­oxy groups of the salicylate ligands. There is one inter­molecular hydrogen-bonding inter­action involving the methanol solvent mol­ecule and the carboxyl­ate group from the monodentate Hsal− ligand. The crystal packing is governed by π–π stacking inter­actions [centroid–centroid distance = 3.783 (4) Å] which occur between bipyridyl ligands, by C—H⋯O and C—H⋯π inter­actions and by numerous van der Waals contacts

Novel inhibition of archaeal family-D DNA polymerase by uracil.

International audienceArchaeal family-D DNA polymerase is inhibited by the presence of uracil in DNA template strands. When the enzyme encounters uracil, following three parameters change: DNA binding increases roughly 2-fold, the rate of polymerization slows by a factor of ≈ 5 and 3'-5' proof-reading exonuclease activity is stimulated by a factor of ≈ 2. Together these changes result in a significant decrease in polymerization activity and a reduction in net DNA synthesis. Pol D appears to interact with template strand uracil irrespective of its distance ahead of the replication fork. Polymerization does not stop at a defined location relative to uracil, rather a general decrease in DNA synthesis is observed. 'Trans' inhibition, the slowing of Pol D by uracil on a DNA strand not being replicated is also observed. It is proposed that Pol D is able to interact with uracil by looping out the single-stranded template, allowing simultaneous contact of both the base and the primer-template junction to give a polymerase-DNA complex with diminished extension ability

Rushes video summarization using a collaborative approach

This paper describes the video summarization system developed by the partners of the K-Space European Network of Excellence for the TRECVID 2008 BBC rushes summarization evaluation. We propose an original method based on individual content segmentation and selection tools in a collaborative system. Our system is organized in several steps. First, we segment the video, secondly we identify relevant and redundant segments, and finally, we select a subset of segments to concatenate and build the final summary with video acceleration incorporated. We analyze the performance of our system through the TRECVID evaluation

Direct Evidence for Octupole Deformation in 146^{146}Ba and the Origin of Large E1E1 Moment Variations in Reflection-Asymmetric Nuclei

Despite the more than one order of magnitude difference between the measured dipole moments in $^{144}$Ba and $^{146}$Ba, the strength of the octupole correlations in $^{146}$Ba are found to be as strong as those in $^{144}$Ba with a similarly large value of $B(E3;3^- \rightarrow 0^+)$ determined as 48($^{+21}_{-29}$) W.u. The new results not only establish unambiguously the presence of a region of octupole deformation centered on these neutron-rich Ba isotopes, but also manifest the dependence of the electric dipole moments on the occupancy of different neutron orbitals in nuclei with enhanced octupole strength, as revealed by fully microscopic calculations.Comment: 6 pages, 5 figures, accepted for publication in Phys. Rev. Let

Expression, purification, crystallization and preliminary X-ray analysis of the cathelicidin motif of the protegrin-3 precursor

International audienc

A collaborative approach to video summarization

This poster describes an approach to video summarization based on the combination of several decision mechanisms provided by the partners of the KSpace European Network of Excellence. The system has been applied to the TRECVID 2008 BBC rushes summarization task