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Method of moments and the use of multipole expansion

In electromagnetic boundary value problems integral equations involving the free space Green function for the Helmholtz equation often occur. Using the method of moments to numerically solve such an equation a matrix equation is obtained. The entries of the matrix are given as multidimensional integrals which in general have to be calculated numerically. This paper presents an efficient method to

Simulation of adaptive optics for the Vacuum Tower Telescope

A simulation model of the adaptive optics of the German Vacuum Tower Telescope (VTT), Observatorio del Teide, Tenerifes presented. The model uses modules from the integrated model of the Euro50 extremely large telescope, and includes submodels of a Shack-Hartmann wavefront sensor, a de-formable mirror, a tip-tilt mirror, high-voltage amplifier low-pass filters, a reconstructor and a controller. We

"Smoothed histograms": a visual aid for the analysis of distributions of muscle fiber areas

The Kernel Density Estimator (KDE) is a versatile nonparametric technique with very good theoretical properties. It is used to obtain "smoothed histograms," which allows several distributions to be presented and analyzed more easily on one graph, and direct combination into average distributions. The application of the KDE method as a visual aid for the analysis of distributions of muscle fiber ar

Diffusion in gels containing immobilized cells - A critical review

Eleven experimental investigations of diffusion in gels containing immobilized cells are reviewed. The experimental data, which quantitatively express the diffusion coefficient as a function of the cell concentration, are compared with a number of well-known equations developed for mass transfer in heterogeneous media. Based on this comparison, a procedure for the theoretical prediction of effecti

Heparan sulfate proteoglycan as a plasma membrane carrier

The plasma membrane defines the border of living cells and provides a barrier to extracellular components. Advances in molecular biology have resulted in the development of novel therapeutic strategies (e.g. gene therapy and cellular protein delivery) which rely on the entry of charged macromolecules into the intracellular compartment. Recent reports demonstrate an intriguing role for heparan sulf

Meat intake and bladder cancer in a prospective study: a role for heterocyclic aromatic amines?

Objective The suspect carcinogens, heterocyclic amines (HAAs), found in well-done meat require host-mediated metabolic activation before inducing DNA mutations. The role of SULT1A1 and of NAT2 on the activation of HAAs suggests that NAT2 rapid acetylator genotype and SULT1A1 allele variants can have an effect on HAA carcinogenicity. Methods Data were collected as part of a case-control study neste

Structural changes in the developing retina maintained in vitro.

The present study examined the emergence of structural remodeling in explanted neonatal rat retina. Immunohistochemical analysis demonstrated signs of glial and neuronal remodeling after I I days in vitro and included the activation of Muller cells, the formation of ectopic neuropil areas and sprouting of photoreceptor terminals. We also observed that cholinergic and GABA-ergic amacrine cells disp

Apolipoproteins A-I and B in obese children

Body mass index (BMI), the distribution of fat, birth weight, physical fitness, apolipoproteins (apo) A-I and B, total cholesterol (TC), and high-density lipoprotein cholesterol (HDLC) were studied in 38 obese 10- to 11-year-olds in comparison to 52 age-matched controls. Obese children had higher concentration of apo B and a lower apo A-I:B ratio. Significant correlations were found between (a) ap

Molecular phylogenetic analysis of circumnuclear hemoproteids (haemosporida, haemoproteidae) of sylviid birds, with description of haemoproteus parabelopolskyi sp. Nov.

Haemoproteus spp., with circumnuclear gametocytes and tentatively belonging to Haemoproteus belopolskyi, are widespread and prevalent in warblers belonging to the Sylviidae, with numerous mitochondrial cytochrome b (cyt b) lineages detected among them.We sampled the hemoproteids from 6 species of warblers adjacent to the Baltic Sea. Parasites were identified to species based on morphology of their

Brood sex ratios, female harem status and resources for nestling provisioning in the great reed warbler (Acrocephalus arundinaceus)

The theory of parental investment and brood sex ratio manipulation predicts that parents should invest in the more costly sex during conditions when resources are abundant. In the polygynous great reed warbler, Acrocephalus arundinaceus. females of primary harem status have more resources for nestling provisioning than secondary females, because polygynous males predominantly assist the primary fe

Situated cognition, dynamic systems and art

It is argued that the theory of situated cognition together with dynamic systems theory can explain the core of artistic practice and aesthetic experience, and furthermore paves the way for an account of how artist and audience can meet via the artist’s work. The production and consumption of art is an embodied practice, firmly based in perception and action, and supported by features of the local

Resistant starch formation in temperature treated potato starches varying in amylose/amylopectin ratio

Two genetically modified potato starches derived from the same mother line (64%, 1% and 23% amylose, respectively) were used to study the bioavailability after various heat treatments. The conditions for the treatments were of minor importance for resistant starch (RS) formation and hydrolysis results, as compared to the proportion of amylose. A high amylose content gave lower hydrolysis index (HI

Quantum Chemical Study of the Influence of Anchor-Cum-Spacer Groups on Femtosecond Electron Transfer Times in Dye-Sensitized Semiconductor Nanocrystals

Electronic properties of dye-sensitized semiconductor nanocrystals, consisting of perylene (Pe) chromophores attached to 2 nm TiO2 nanocrystals via different anchor-cum-spacer groups, have been studied theoretically using density functional theory (DFT) cluster calculations. Approximate effective electronic coupling strengths for the heterogeneous electron-transfer interaction have been extracted

An esterolytic imprinted polymer prepared via a silica-supported transition state analogue

In this work we describe a new preparation method for an esterolytic imprinted polymer with catalytic sites on the surface. A template was prepared by immobilizing a transition state analogue (phosphoramidic acid derivative) of an esterolytic reaction within porous silica particles. Polymerization within the pores was carried out using 4-vinylimidazole as a functional monomer and divinylbenzene as

Association of a microsatellite in FASL to type II diabetes and of the FAS-670G > A genotype to insulin resistance

Type II diabetes is caused by a failure of the pancreatic beta-cells to compensate for insulin resistance leading to hyperglycaemia. There is evidence for an essential role of an increased beta-cell apoptosis in type II diabetes. High glucose concentrations induce IL-1 beta production in human beta-cells, Fas expression and concomitant apoptosis owing to a constitutive expression of FasL. FASL and

Variants of the interleukin-1 receptor antagonist gene are associated with fat mass in men

Context: Immune functions seem to have connections to variations in body fat mass. Studies of knockout mice indicate that endogenous interleukin (IL)-1 can suppress mature-onset obesity. Objective: To systematically investigate our hypotheses that single- nucleotide polymorphisms (SNPs) and/or haplotypes variants in the IL-1 gene system are associated with fat mass. Subjects: The Gothenburg osteop