Objective: Evaluate the protective effect of artificial saliva formulations associated or not with mucin on dentin. Materials and Methods: Bovine dentin specimens were randomly allocated to 10 groups (n = 20) according tested presence absence mucin: Amaechi et al. (1998); Klimek (1982); Vieira (2005) Eisenburger (2001) deionized water (control). Samples submitted an erosive cycle consisting two...

this paper presents a new arc starter circuit that is usable in manual metal arc welding (mma) power supplies. the proposed circuit uses an auxiliary circuit and a series coupling transformer for adding high frequency spikes to output dc voltage during arc striking. the proposed circuit is usable in inverter based arc welding supplies and it could result in a decrease of weigh, volume and expen...

introduction : arsenic trioxide (as2o3) causes antitumor effects by various mechanisms, including degradation of pml-rara in the acute promyelocytic cells, growth inhibition and induction of apoptosis. however, the precise mechanisms of these processes remain incompletely understood. the purpose of this study was to evaluate the effects of arsenic trioxide on cell growth, cell cycle regulation ...

we give a new recursive method to compute the number of cliques and cycles of a graph. this method is related, respectively to the number of disjoint cliques in the complement graph and to the sum of permanent function over all principal minors of the adjacency matrix of the graph. in particular, let $g$ be a graph and let $overline {g}$ be its complement, then given the chromatic polynomial of...

we present a matching and lp based heuristic algorithm that decides graph non-hamiltonicity. each of the n! hamilton cycles in a complete directed graph on n + 1 vertices corresponds with each of the n! n-permutation matrices p, such that pu,i = 1 if and only if the ith arc in a cycle enters vertex u, starting and ending at vertex n + 1. a graph instance (g) is initially coded as exclusion set ...

let g be a (p, q) graph. let k be an integer with 2 ≤ k ≤ p and f from v (g) to the set {1, 2, . . . , k} be a map. for each edge uv, assign the label |f(u) − f(v)|. the function f is called a k-difference cordial labeling of g if |νf (i) − vf (j)| ≤ 1 and |ef (0) − ef (1)| ≤ 1 where vf (x) denotes the number of vertices labelled with x (x ∈ {1, 2 . . . , k}), ef (1) and ef (0) respectively den...

Ovulation rate in gilts maintained under continuous light (daylight plus 118 to 130 lux of artificial light at night) for a complete oestrous cycle during the spring months was not significantly different from that in gilts maintained under normal daylight. Average ovulation rates were 13\m=.\4for controls and 13\m=.\1for treated gilts. A significant (P<0\m=.\01)difference in ovulation rate was...

Dioxygen activation at copper(i) centres is of primary importance for the development of sustainable oxidation catalysis, but regeneration of copper(i) centres after each catalytic cycle remains a major problem for multi-turn-over catalysis. This work demonstrates that an artificial reductase, made of flavin cofactors incorporated into a water soluble polymer, efficiently reduces a Cu(ii)TPA co...