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Projective limits of Banach algebras have been studied sporadically by many authors since 1952, when they were first introduced by Arens [2] and Michael [11]. Projective limits of complex C∗-algebras were first mentioned by Arens [2]. They have since been studied under various names by Wenjen [20], Sya Do-Shin [18], Brooks [4], Inoue [10], Schmüdgen [17], Fritzsche [6–7], Fragoulopoulou [5], Ph...

If X is a topological space, then we let H(X) denote the group of autohomeomorphisms of X equipped with the compact-open topology. For subsets A and B of X we define [A, B] = {h ∈ H(X) : h(A) ⊂ B}, and we recall that the topology on H(X) is generated by the subbasis SX = {[K , O] : K compact, O open in X}. If X is a compact Hausdorff space, then H(X) is a topological group, that is, composition...

We investigate the Arens products on the biduals of certain algebras of operators on nonreflexive Banach spaces. To be precise, we study the α-nuclear operators, where α is a tensor norm. This includes the approximable and nuclear operators, and we use these, together with the 2-nuclear operators, as motivating examples. The structure of the two topological centres of the bidual are studied, an...

The metabolism of vitamin A Formation of retinof, retinyl esters and retinal. Dietary provitamins and vitamin A are sources of tissue deposits of retinol, retinyl esters and retinal; the latter substances constitute a storage and transport system (Ganguly, 1960) which allows a continuous supply of the active form of the vitamin to be provided at whatever site it is required. T h e alcohol, alde...