The synthesis of XTT: A new tetrazolium reagent that is bioreducible to a water-soluble formazan

A new tetrazolium salt, XTT, has been synthesized. XTT is reduced by a considerable variety of cell lines to a water-soluble formazan. XTT appears to merit further investigation as a reagent for broader application to cell culture assay systems.     

The folded, tetrameric phosph(III)azane macrocycle [(P(mu-NtBu))2(1,4-(NH)2C6H4)]4

The tetrameric macrocycle [(P(mu-NtBu))2(1,4-(NH)2C6H4)]4, obtained from the reaction of the phosphazane dimer [ClP(mu-NtBu)]2 with p-phenylenediamine, has an unusual folded conformation in the solid state and contains a roughly tetrahedral arrangement of endo N-H groups for the potential coordination of anions.     

An Almost Prime Element in a Commutative Radical Banach Algebra

Thomas conjectured that there is no such thing as an almostprime element in a commutative radical Banach algebra. Thispaper shows that there is such an element. However, it stillleaves open the question of whether there is an element thatis almost prime, but not prime. 2000 Mathematics Subject Classification46J40, 46J45.     

An upper bound for a percolation constant

Résumé Dans cette note, nous étudions le temps minimum que prend un fluide pour se répandre à travers un milieu quand les temps nécessaires pour traverser les arcs du milieu sont des variables aléatoires indépendantes les unes des autres et tirées de la distribution uniforme et rectangulaire.