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Transient electromagnetic wave propagation in transverse periodic media

In this paper, a time-domain technique is used to analyze the wave propagation of electromagnetic pulses in media that are periodic in one spatial direction, perpendicular to the direction of propagation. The wave equation is reduced to a system of one-dimensional first order time dependent hyperbolic equations by a Fourier expansion in the transverse spatial direction and by utilizing a wave spli

Endothelial dysfunction after repeated Chlamydia pneumoniae infection in apolipoprotein E-knockout mice

BACKGROUND: Arterial relaxation is largely regulated by endothelial nitric oxide (NO). Its diminished activity has been associated with incipient atherosclerosis. We investigated the endothelium-dependent relaxation of aorta in apolipoprotein E-knockout (apoE-KO) mice exposed to single or repeated Chlamydia pneumoniae inoculation. METHODS AND RESULTS: Forty-eight apoE-KO mice, 8 weeks old, were in

Intermediate phases observed during decomposition of LiBH4

Lithium tetrahydridoboranate is among the materials with the highest hydrogen content and has great potential as a possible H-2-storage material, although, the release and uptake of H-2 is not fully understood. In this work, LiBH4 was studied by in situ synchrotron radiation powder X-ray diffraction (PXD) and solid state CP/MAS NNIR both at variable temperatures. This study revealed two new phases

{mu-2-[1-(N,N-Dimethylamino)ethyl]ferrocene-1,1 '-diylbis(diphenylphosphine)-kappa P-2 : P '}-bis[chlorogold(I)]

The structure of the title compound, [ Au2Fe( C21H23NP)( C17H14P) Cl-2], displays the pseudo-linear [ P - Au - Cl = 175.4 ( 1) and 174.0 ( 1) degrees] two-coordinate geometry usually observed in gold( I) complexes. The Au - P bond distances are 2.237 ( 2) and 2.224 ( 2) angstrom and the Au - Cl distances are 2.271 ( 3) and 2.278 ( 2) angstrom. The bis( diphenylphosphino)ferrocenyl ligand links the

Increasing the degree of automation in a production system: Consequences for the physical workload

In spite of the continuous development of production systems work-related musculoskeletal disorders is still a large problem. One reason might be the difficulties in quantifying the ergonomic effects of interventions. In this paper ergonomic consequences of technical and organisational changes were quantified in a plant for producing slats for parquet flooring. Muscle activity, work postures and m

DEGENERATIVE CHANGES OF THE HUMAN TEMPOROMANDIBULAR JOINT: A radiological, microscopical, histomorphometrical and biochemical study.

Popular Abstract in Swedish I fem autopsistudier undersöktes humana käkledspreparat med tomografi (skiktröntgen), makroskopiskt (inspektion) och mikroskopiskt för förekomst av degenerativa (nedbrytande) förändringar. Speciellt undersöktes förekomst av erosiva förändringar i benet samt förändringar i den förkalkade broskzonen (skiktet mellan mjukbrosk och ben). Det förkalkade brosket var i normalaIn five autopsy specimen studies human temporomandibular joints were investigated by conventional tomography, macroscopy, and microscopy for degenerative changes, in particular erosive hard-tissue changes.In the microscopical evaluation special attention was paid to the calcified cartilage. The calcified cartilage was outlined by a flat or gently undulating basophilic tidemark and an irregular os

Optimal Bayesian foraging policies and prey population dynamics - Some comments on Rodriguez-Girones and Vasquez

In this paper we show the density-dependent harvest rates of optimal Bayesian foragers exploiting prey occurring with clumped spatial distribution. Rodriguez-Girones and Vasquez (1997) recently treated the issue, but they used a patch-leaving rule (current value assessment rule) that is not optimal for the case described here. An optimal Bayesian forager exploiting prey whose distribution follows

The Transient Response Technique for the Study of Hydrocarbon Oxidation on Metal Oxides: Simulation of the Responses for Various Propene Oxidation Mechanism

Partial differential equations, describing the consumption of reactants and the formation of products, have been solved numerically for a step change from inert to reactant feed considering different variants of propene oxidation mechanisms. The response features and their dependency on the rate limiting step have been rationalised in terms of conclusions, which can serve as general guidelines for

Biodiversity at Linnaeus' birthplace in the parish of Stenbrohult, southern Sweden. 5. Butterflies and burnet moths.

We counted butterflies in almost all open grasslands in an area of 8000 hectare over five years (2001-2005) in the central part of the parish of Stenbrohult, southern Sweden (Fig. 1; 56 degrees 37' N, 14 degrees 11' O). This area is currently dominated by forests. Grasslands, mainly grazed by cattle and horses, only cover about 6 % of the area. The study area consisted of 18 farms, most ot them ar

Gene expression changes in the course of neural progenitor cell differentiation

The molecular changes underlying neural progenitor differentiation are essentially unknown. We applied cDNA microarrays with 13,627 clones to measure dynamic gene expression changes during the in vitro differentiation of neural progenitor cells that were isolated from the subventricular zone of postnatal day 7 mice and grown in vitro as neurospheres. In two experimental series in which we withdrew

Chaotic electrical activity of living beta-cells in the mouse pancreatic islet

To test for chaotic dynamics of the insulin producing beta-cell and explore its biological role, we observed the action potentials with the perforated patch clamp technique, for isolated cells as well as for intact cells of the mouse pancreatic islet. The time series obtained were analyzed using nonlinear diagnostic algorithms associated with the surrogate method. The isolated cells exhibited shor

Relationship between somatic cell count, individual leukocyte populations and milk components in bovine udder quarter milk

The somatic cell count (SCC) in bovine milk is an indicator of udder health and milk quality. Individual cell populations, i.e., macrophages, lymphocytes and polymorphonuclear neutrophils, were identified and their relationship to milk components such as acute-phase proteins (serum amyloid A (SAA) and alpha(1)-acid glycoprotein), lactic acid and lactoferrin (LF), as well as protein, fat and lactos

Electric dipole strength below the giant dipole resonance

Recent experimental findings and theoretical approaches to the electric dipole (El) strength distribution below the particle emission threshold at shell closures are revisited. Results from photon scattering experiments are discussed and compared to predictions within the quasiparticle-phonon nuclear model. An analysis of the fine structure of the El strength is presented. Recent studies of the E1

Chemiluminescence of 1,2-dioxetane. Reaction mechanism uncovered

The thermal decomposition of 1,2-dioxetane and the associated production of chemiluminescent products, model for a wide range of chemiluminescent reactions, has been studied at the multistate multiconfigurational second-order perturbation level of theory. This study is in qualitative and quantitative agreement with experimental observations with respect to the activation energy and the observed in

Epicardial right atrial free wall mapping in chronic atrial fibrillation. Documentation of repetitive activation with a focal spread--a hitherto unrecognised phenomenon in man

BACKGROUND: Previous studies have shown that atrial fibrillation of recent onset in man is based on a varying number of simultaneously present activation waves reentering either themselves or each other. In the present study, right atrial activation during chronic atrial fibrillation in man was studied. METHODS AND RESULTS: In 16 patients with chronic atrial fibrillation multiple epicardial record