We report a sequence reconstruction analysis targeting several Precambrian nodes in the evolution of class-A β-lactamases and the preparation and experimental characterization of their encoded proteins. Despite extensive sequence differences with the modern enzymes (~100 amino acid differences), the proteins resurrected in the laboratory properly fold into the canonical lactamase structure. The...

introduction: the purpose of this study was to investigate the effect of flask investment materials on the color changes of different brands of resin denture teeth. methods: resin denture teeth (560) were divided into 2 groups according to the materials used for flask investment (silicone or gypsum). all the specimens were thermocycled between 4°c and 60°c with 60-s dwell times for 1,000 cycles...

In commercial and recreational fisheries, catch rate is often assumed to be proportional stock size used by managers fishers as an indicator of fishery sustainability. If size, it can signal a decline stocks impose restrictive harvest policies or anglers move new system allow the over-exploited rebound. A growing literature has documented rates remaining high even fish (i.e., hyperstability rat...

To be useful for extremely stiff systems of ordinary differential equations, A -stability and a maximally damped condition as \h -* °° (i.e., L-stability) are desirable. This paper investigates the condition of ¿-stability for a class of Runge-Kutta methods known as the Rosenbrock procedure. This procedure requires only one computation of a Jacobian matrix per step of integration, ¿-stable Rose...

We propose a model of discrete time dynamic congestion games with atomic players and a single source-destination pair. The latencies of edges are composed by free-flow transit times and possible queuing time due to capacity constraints. We give a precise description of the dynamics induced by the individual strategies of players and of the corresponding costs, either when the traffic is control...

Every finite group acts as the full isometry group of some compact hyperbolic 3-manifold. In this paper we study those finite groups which act maximally, that is when the ratio |Isom(M)|/vol(M) is maximal among all such manifolds. In two dimensions maximal symmetry groups are called Hurwitz groups, and arise as quotients of the (2,3,7)–triangle group. Here we study quotients of the minimal co-v...

In this note we propose and analyze an implicit-explicit scheme based on second order strong stability preserving time discretisations. We also present some theoretical and numerical stability results for second order Runge Kutta IMEX schemes.