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...

The Ph(4)P(+) salt of the tetrahedral complex [Co(SPh)(4)](2-), possessing an S = (3)/(2) ground state with an axial zero-field splitting of D = -70 cm(-1), displays single-molecule magnet behavior in the absence of an applied magnetic field. At very low temperatures, ac magnetic susceptibility data show the magnetic relaxation time, τ, to be temperature-independent, while above 2.5 K thermally...

Acute lung injury (ALI) is characterized by lung inflammation and diffuse infiltration of neutrophils into the alveolar space. The inhibition of alveolar neutrophil apoptosis has been implicated in the pathogenesis of ALI. Although sphingolipids may regulate cell apoptosis, the role of sphingolipids in activated neutrophils during ALI is not clear. In this study, we test the hypothesis that sph...

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...

The objective of the present study is to develop and investigate the swelling behavior of pH-sensitive Superporous Hydrogel (SPH) and SPH composite (SPHC). A novel superporous hydrogel containing poly (methacrylic acid-co-acrylamide) was synthesized from methacrylic acid and acrylamide through the aqueous solution polymerization, using N,N-methylenebisacrylamide as a crosslinker and ammonium pe...

Secretory type II phospholipase A2 (sPLA2) is inhibited by sphingomyelin (SPH); cholesterol either mixed with the model glycerophospholipid substrate or added to the assay medium as separated liposomes counteracts this inhibition efficiently. The inhibition of fatty acid release assayed by quantitative gas chromatography-MS is observed when SPH is added to erythrocyte membranes as the substrate...

We present an application of SPH to saturated soil problems. Herein, the standard SPH formulation was improved to model saturated soil. It is shown that the proposed formulation could yield several advantages such as: it takes into account the pore-water pressure in an accurate manner, it automatically satisfies the dynamics boundary conditions between submerged soil and water, and it reduced t...

The time-independent one-speed neutron transport equation for media with sphericallysymmetric invariance properties and an isotropic scattering law is discussed. The analysis allowsfor isotropic internal emission, and emphasis is placed on the treatment of neutrons incident onthe free surface of a finite spherical medium. ZusammenfassungGegenstand diese Artikels ist eine zei...