Abelian cocycles for nonsingular ergodic transformations and the genericity of type III1 transformations

The authors prove that in the space of nonsingular transformations of a Lebesgue probability space the type III₁ ergodic transformations form a denseG set with respect to the coarse topology. They also prove that for any locally compact second countable abelian groupH, and any ergodic type III transformationT, it is generic in the space ofH-valued cocycles for the integer action given byT that the skew product ofT with the cocycle is orbit equivalent toT. Similar results are given for ergodic measure-preserving transformations as well.Research supported in part by: Nat. Sci. and Eng. Res. Council #A7163 and # U0080 F.C.A.C. Quebec, NSF Grants # MCS-8102399 and # DMS-8418431.     

Development and validation of an HPLC stability-indicating method for identification and assay of elemental iron(II) in pharmaceutical drug products using reversed-phase HPLC

Ferrous sulfate tablets are a supplementary iron source for people who suffer from iron deficiency anemia. A simple, fast, and QC-friendly HPLC method was developed and validated to determine elemental iron in ferrous sulfate drug products. A TSK-GEL Super octadecylsilyl column (50 x 4.6 mm id, 2 microm particle size) with a mobile phase consisting of 0.06 M methanesulfonic acid in water-acetonitrile (40 + 60, v/v) and UV detection at 282 nm were used for this method. Separation of the elemental iron peak from the matrix was achieved within 5 min. This method was successfully validated according to International Conference on Harmonization guidelines, and shown to be stability-indicating for the shelf-life samples of ferrous sulfate tablets, as well as selective for the analyte of interest.     

Automorphisms of baire measures on generalized cubes. II

Probability Theory and Related Fields -     

A change of variables formula for mappings in

A change of variables formula for mappings in is obtained, where the usual jacobian is replaced by the determinant of the approximate differential.

     

Mechanism of base-catalyzed autooxidation of corticosteroids containing 20-keto-21-hydroxyl side chain

Corticosteroids and related compounds containing the 20-keto-21-hydroxyl side chain such as betamethasone, betamethasone 9,11-epoxide, dexamethasone, and dexamethasone 9,11-epoxide have been found to undergo facile autooxidation on the 1,3-dihydroxyacetone side chain of their D-rings under strong alkaline conditions to yield five main degradants (17-formyloxy-17-acid, 17-acid, 21-aldehyde, 20-hydroxy-21-acid, and 17-ketone). The rate of the autooxidation was correlated with the strength and concentration of the base used in the reaction. A novel mechanism for the observed autooxidation is proposed, in which the facile oxidation of the presumed enolate (resulting from the carbanion at the 21-position) by molecular oxygen is the key step. The proposed autooxidation mechanism, supported by LC-MS isotope experiments using ¹⁸O₂ as the oxidant, can satisfactorily explain the oxidative degradation patterns observed for corticosteroids containing the 20-keto-21-hydroxyl side chain.     

Assay of Ivermectin Including Determination and Identification of Its Related Substances in Ivermectin Injectable Product by a Stability-Indicating RP-HPLC Method

Chromatographia - Ivermectin injectable product is widely used as a parasiticide for the treatment and control of internal and external parasites of cattle and swine. A reversed-phase high...