This paper considers the possibility of spontaneous transition of aracemic mixture (composed of equal amounts of two enantiomeric species, say L and D) into a monochiral state (in which only one enantiomer, say L, is present). Transitions of this kind have been recently experimentally observed. A plausible approach to this phenomenon is a model put forward by Frank, based on simple laws of ...

this paper considers the possibility of spontaneous transition of aracemic mixture (composed of equal amounts of two enantiomeric species, say l and d) into a monochiral state (in which only one enantiomer, say l, is present). transitions of this kind have been recently experimentally observed. a plausible approach to this phenomenon is a model put forward by frank, based on simple laws of chem...

the problem of finding the minimum cost multi-commodity flow in an undirected and completenetwork is studied when the link costs are piecewise linear and convex. the arc-path model and overflowmodel are presented to formulate the problem. the results suggest that the new overflow model outperformsthe classical arc-path model for this problem. the classical revised simplex, frank and wolf and a ...

There are few reports concerning interferon induced myocardial dysfunction. A known case of multiple myeloma who was receiving interferon alpha (IFA) for 14 months was brought to the emergency room in frank: pulmonary edema. After treatment of heart failure and discontinuation of interferon alpha, he remained asymptomatic thereafter. Another case of chronic active hepatitis on IFA complain...

In a digraph D = (X,U) , not necessarily finite, an arc (x, y) ∈ U is reachable from a vertex u if there exists a directed walk W that originates from u and contains (x, y) . A subset S ⊆ X is an arc-reaching set of D if for every arc (x, y) there exists a diwalk W originating at a vertex u ∈ S and containing (x, y) . A minimal arc-reaching set is an arc-basis. S is a point-reaching set if for ...

If sk denotes the number of stable sets of cardinality k in graph G, and α(G) is the size of a maximum stable set, then I(G;x) = α(G) ∑ k=0 skx k is the independence polynomial of G (Gutman and Harary, 1983). A graph G is very well-covered (Favaron, 1982) if it has no isolated vertices, its order equals 2α(G) and it is well-covered (i.e., all its maximal independent sets are of the same size, M...

A generalisation of a perturbed version of the Ostrowski inequality for twice differentiable mappings is studied. It is shown that the error bounds are better than those obtained previously. Applications for general quadrature formulae are also given.