Measurement of the Lambdab0 lifetime using semileptonic decays

We report a measurement of the Lambda(b)(0) lifetime using a sample corresponding to 1.3 fb(-1) of data collected by the D0 experiment in 2002-2006 during run II of the Fermilab Tevatron collider. The Lambda(b)(0) baryon is reconstructed via the decay Lambda(b)(0)-->micronuLambda(c)(+)X. Using 4437+/-329 signal candidates, we measure the Lambda(b)(0) lifetime to be tau(Lambda(b)(0))=1.290(-0.110)(+0.119)(stat)(-0.091)(+0.087)(syst) ps, which is among the most precise measurements in semileptonic Lambda(b)(0) decays. This result is in good agreement with the world average value.     

Stereoselective Reduction of δ-Hydroxy-β-ketoesters

The reduction of δ-hydroxy-β-ketoesters 1 was investigated with three different reducing agents. In several instances, high selectivity in favor of syn-1,3-diols was observed.     

Antiparasitic activities of bimetallic N-heterocyclic carbene gold(I) complexes with ferrocene ligands: Relevance of chlorido and phosphino ligands

Gold(I) complexes carrying imidazole-2-ylidene ligands and ferrocene substituents were prepared. Their activities against protozoal Leishmania major and Toxoplasma gondii parasites were analyzed. Certain gold(I) complexes with chlorido and 1,1′-bis(triphenylphosphino)ferrocene ligands revealed promising antiparasitic effects. The new chlorido complexes 5b and 5c showed high activities against T. gondii tachyzoites and L. major promastigotes while the new ferrocene-bridged bis-gold(I) complexes 8a and 8b were particularly active against L. major amastigotes and considerably selective as to toxicity results from Vero cells and macrophages.     

Extremal Rational Functions on Symmetric Discrete Sets and Superlinear Convergence of the ADI Method

There is a very fruitful interaction between numerical linear algebra and logarithmic potential theory. For instance, we may describe weak asympotics for a polynomial extremal problem occurring in the convergence analysis of conjugate gradients (CG) or of Ritz values; here the link with a constrained minimal energy problem allows to quantify the effect of superlinear convergence.     

Smooth Fréchet globalizations of Harish-Chandra modules

We give an alternative proof of the Casselman-Wallach globalization theorem. The approach is based on lower bounds for matrix coefficients on a reductive group.     

Trialkylaluminum N-Heterocyclic Olefin (NHO) Adducts as Catalysts for the Polymerization of Michael-Type Monomers

The synthesis of new trialkylaluminum adducts with N-heterocyclic olefin (NHO) ligands is described. These well-defined complexes can catalyze the polymerization of various Michael-type monomers, such as 2-vinylpyridine, methylacrylate, and dimethylacrylamide.