The serum-borne lysophospholipid mediators sphingosine 1-phosphate (Sph-1-P) and lysophosphatidic acid (LPA) have been shown to be released from activated platelets and to act on endothelial cells. In this study, we employed the repeated lipid extraction (under alkaline and acidic conditions), capable of detecting Sph-1-P, LPA, and possibly structurally similar lysophospholipids, whereby a mark...

By comparing a collisionless cosmological N-body simulation (DM) to a smoothed particle hydrodynamics simulation (SPH) with the same initial conditions, we investigate the correspondence between the dark matter subhalos produced by collisionless dynamics and the galaxies produced by dissipative gas dynamics in a dark matter background. When galaxies in the SPH simulation fall into larger groups...

In order to determine whether sphingomyelin (SPH) affects the rate of cholesterol esterification by plasma lecithin-cholesterol acyltransferase (LCAT), we studied the effects of its incorporation in to defined proteoliposome substrates containing phosphatidyl choline (PC), unesterified cholesterol, and apoprotein A-I, on the activity of purified LCAT. Cholesterol esterification was inhibited by...

We report on the metal ion exchange between Co(2+) and CdS-based molecular clusters. These studies demonstrate that exchange into the smaller [Cd4(SPh)10](2-) clusters is facile compared to the larger [Cd10S4(SPh)16](4-) and [Cd17S4(SPh)28](2-) clusters. This trend correlates with the rate of benzenethiolate interconversion and μ-S(2-) and μ-SPh(-) content among the clusters.

PURPOSE To describe spherical equivalent (sph eq) refractive errors in preschool members of a Native American tribe with a high prevalence of astigmatism. METHODS Cycloplegic autorefraction measurements were obtained for 819 three- and four-year-old Tohono O'odham children, with follow-up measurements in 146 after 4 to 8 years. RESULTS Mean sph eq was significantly more hyperopic in the ast...

The smoothed particle hydrodynamics (SPH) method is a useful numerical tool to study a variety of astrophysical and planetlogical problems. However, it turned out that the standard SPH algorithm has problems in dealing with hydrodynamical instabilities. This problem is due to the assumption that the local density distribution is differentiable. In order to solve this problem, a new SPH formulat...

In 2007, the results from a comparison study of grid based codes and SPH codes on multiphase interactions in compressible fluids were presented [1]. The main conclusion from this study was that whilst the grid codes are able to describe important dynamical instabilities, such as KelvinHelmholtz (KH) and Richtmyer-Meshkov (RM), these processes are poorly described by existing SPH codes. It was l...

BACKGROUND Ceramide (Cer) and sphingosine (Sph) interfere with critical cellular functions relevant for cancer progression and cell survival. While Cer has already been investigated as a potential drug target for lymphoma treatment, information about the potency of sphingosine is scarce. The aim of this study therefore was to evaluate Sph and its synthetic stereoisomer L-threo-sphingosine (Lt-S...

Let X be a finite CW-complex. Denote by Sph(X) the abelian group of stable fibre-homotopy classes of spherical fibrations on X. Let F (n) be the monoid of self-homotopy-equivalences of S and let F := colimn→∞ F (n). The classifying space BF represents Sph(X), i.e. Sph(X) ∼= [X;BF ]. For any vector bundle ξ on X, let J(ξ) ∈ Sph(X) be the stable fibre homotopy class of the spherical fibration ξ \...

In this paper, the applications of mesh-free SPH (Smoothed Particle Hydrodynamics) methodology to the simulation and analysis of 3-D hard machining process is presented. A Langrangian SPH based model is carried out using the Ls-Dyna software. Classical Lagrangian, Eulerian and ALE methods such as finite element methods (FEM) cannot resolve the large distortions very well. Conventional finite el...