We prove that the strong product G1 G2 of G1 and G2 is Z3-flow contractible if and only if G1 G2 is not T K2, where T is a tree (we call T K2 a K4-tree). It follows that G1 G2 admits an NZ 3-flow unless G1 G2 is a K4-tree. We also give a constructive proof that yields a polynomial algorithm whose output is an NZ 3-flow if G1 G2 is not a K4-tree, and an NZ 4-flow otherwise. 2009 Wiley Periodical...

CONTEXT To our knowledge, no previous studies examined the longitudinal relationship between vitamin D status and pulmonary function in a population-based sample of older persons. OBJECTIVE Our objective was to examine the cross-sectional as well as the longitudinal relationship between vitamin D status and peak expiratory flow rate (PEFR) in a representative sample of the Dutch older populat...

The benchmark test case for non-orthogonal grid mesh, the “driven skewed cavity flow”, first introduced by Demirdžiü et al. [5] for skew angles of 30 D D and 45 D D , is reintroduced with a more variety of skew angles. The benchmark problem has non-orthogonal, skewed grid mesh with skew angle (D ). The governing 2-D steady incompressible NavierStokes equations in general curvilinear coordinates...

Protein dynamics play a significant role in many aspects of enzyme activity. Monitoring structural changes and aggregation biotechnological enzymes under native conditions is important to safeguard their properties function. In this work, the potential asymmetrical flow field-flow fractionation (AF4) study dynamic association equilibria β-D-galactosidase (β-D-Gal) was evaluated. Three commercia...

The characteristics of flow structures around a colony-type emergent roughness model, hereafter called ‘colony model’, mounted on a flat plate in uniform flow and the drag coefficient Cdc for the colony model are investigated by flow visualization, spectral analysis, velocity measurement and drag force measurement. Two types of colony models, each comprising seven equally spaced cylinders with ...