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Nanoimprinted passive optical devices

We report on the feasibility and process parameters of nanoimprint lithography to fabricate low refractive index passive optical devices. Diffraction gratings printed in polymethylmethacrylate (PMMA) exhibit a sharp dispersion with a full width at half maximum of about 20 nm. Waveguides were printed in polystyrene (PS) on silicon oxide and had losses between 8-20 dB cm(-1) at wavelengths between 6

Efficient algorithm for edge cracked geometries

The stress field in a finite, edge cracked specimen under load is computed using algorithms based on two slightly different integral equations of the second kind. These integral equations are obtained through left regularizations of a first kind integral equation. In numerical experiments it is demonstrated that the stress field can be accurately computed. Highly accurate stress intensity factors

Dispersion of atrial repolarization in patients with paroxysmal atrial fibrillation

To study the role of the dispersion of atrial repolarization (DAR) in the genesis of atrial fibrillation (AF), monophasic action potentials (MAP) were recorded simultaneously from a catheter at the high lateral right atrium (HLRA) and a catheter moving around the high, middle and low lateral right atrium (RA) the high, anterior and posterior septal RA and the RA appendage in 15 patients with parox

Chromosome ends in Chironomus tentans do not have long single-stranded overhangs characterizing canonical telomeres.

Single-stranded overhangs of the G-rich strand belong to the conserved features of telomeres composed of short telomeric repeats. These structures are thought to be essential for the maintenance of proper telomeric structure and function and the mechanism of their generation is telomerase-independent. We have examined the presence of single-stranded overhangs in Chironomus tentans, a dipteran inse

Direct evidence of secondary necrosis of neutrophils during intense lung inflammation.

Several pulmonary inflammatory conditions are characterised by infiltration of neutrophils. Normally, neutrophils are silently removed by apoptosis, followed by phagocytosis. However, if phagocytosis fails, apoptotic cells undergo secondary necrosis. Recent findings of increased levels of the pan-necrosis marker lactate dehydrogenase in bronchoalveolar lavage from lipopolysaccharide-exposed mice i

Non-neutral community dynamics: empirical predictions for ecosystem function and diversity from linearized consumer–resource interactions

A general model of linearized species interactions, essentially Lotka–Volterra theory, applied to questions of biodiversity has previously been shown to be a powerful tool for understanding local species–abundance patterns and community responses to environmental change for a single trophic level. Here this approach is extended to predict community composition and responses to environmental change

Dynamic object-oriented heat exchanger models for simulation of fluid property transitions

Object-oriented heat exchanger models were developed to simulate the dynamic thermal effects of dynamic changes in fluid composition and thus of fluid properties in a type of liquid typical for food products. The models were written in the object-oriented language Modelica as objects in a library structure being developed to simulate complex liquid food process lines and their control systems. The

Prompt Alpha Decay of a Well-deformed Band in 58Ni

Two excited well-deformed bands have been observed in the semi-magic nucleus Ni-58. One of the bands was observed to partially decay by emission of a prompt discrete alpha particle that feeds the 2949 keV 6(+) spherical yrast state in the daughter nucleus Fe-54. This constitutes the first observation of prompt alpha emission from states lying in the deformed secondary minimum of the nuclear potent

Cib2 binds integrin a7Bb1D and is reduced in laminin a2 chain deficient muscular dystrophy

Mutations in the gene encoding laminin alpha 2 chain cause congenital muscular dystrophy type 1A. In skeletal muscle, laminin alpha 2 chain binds at least two receptor complexes: the dystrophin-glycoprotein complex and integrin alpha 7 beta 1. To gain insight into the molecular mechanisms underlying this disorder, we performed gene expression profiling of laminin alpha 2 chain-deficient mouse limb

Covalently Linked Ruthenium(II)-Manganese(II) Complexes: Distance Dependence of Quenching and Electron Transfer

Continuing our development of artificial models for photosystem II in green plants, a series of compounds have been prepared in which a Ru(bpy)32+ photosensitizer is covalently linked to a manganese(II) electron donor. In addition to a trispicolylamine ligand, two other manganese ligands, dipicolylamine and aminodiacetic acid, have been introduced in order to study ligands that are appropriate for

Job strain and male fertility

BACKGROUND: Job strain, defined as high job demands and low job control, has not previously been explored as a possible determinant of male fertility. We collected prospective data on job strain among men, and describe the associations with semen quality and probability of conceiving a clinical pregnancy during a menstrual cycle. METHODS: Danish couples (N = 399) who were trying to become pregnant

Interventions in hypothetical elder abuse situations suggested by Swedish formal carers.

In Sweden, public attention has not focused on elder abuse. No common view of interventions or organizational repsonsibilities has been developed. The aim of this study was to describe interventions suggested by Swedish formal carers in three hypothetical, typical cases of elder abuse. From one municipality in Sweden, 71 formal carers (district nurses, home service assistants, and general practiti

Competitive adsorption of proteins from total hen egg yolk during emulsification

In this article, the competitive adsorption of egg yolk proteins at oil/water interfaces during emulsification is studied. By using two-dimensional polyacrylamide electrophoresis and mass spectrometry, it was possible to characterize and identify adsorbing and non-adsorbing protein species. The egg yolk contains proteins with a wide range of molecular weights and pI. Lipoproteins adsorbed selectiv

The impact of testicular carcinoma and its treatment on sperm DNA integrity

BACKGROUND: In patients with testicular germ cell carcinoma (TGCC), spermatogenesis and fertility are impaired. Intracytoplasmic sperm injection has improved their possibility of fatherhood, but might also impose a risk of transmitting DNA defects to the offspring. The aim of the current study was to evaluate the impact of chemotherapy and irradiation on sperm DNA integrity.METHODS: The study incl

Alterations in electroretinograms and retinal morphology in rabbits treated with vigabatrin

PURPOSE: To determine whether long-term treatment with the anti-epileptic drug vigabatrin causes damage to rabbit retina.METHODS: Five rabbits were treated continuously with a daily dose of vigabatrin solution per orally during a period of 1-8 months. Two rabbits receiving water were used as controls. Repeated full-field electroretinograms (every two weeks) were assessed during this period. Vigaba

Synthesis of a C-glycoside analogue of beta-D-galactosyl hydroxynorvaline and its use in immunological studies

A C-linked isostere of beta-D-galactosylated hydroxynorvaline has been prepared in eight steps from per-O-benzylated galactopyranolactone. Addition of a homoallylic Grignard reagent to the lactone, reduction of the resulting hemiacetal with triethylsilane, and a Wittig reaction with Garner's aldehyde were key steps in this synthesis. The C-linked building block was then incorporated at position 26