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Neutrophil recruitment in mast cell-dependent inflammation: inhibitory mechanisms of glucocorticoids

Mast cells are strategically localized along the microvasculature in tissues in close contact with the external environment, such as the skin, lung and intestines. By releasing a multi-faceted spectrum of proinflammatory mediators, such as cytokines and chemokines, mast cells have the capacity to coordinate trafficking of leukocytes. Mast cells play a pathophysiological role in numerous inflammato

Structural basis of the iron storage function of frataxin from single-particle reconstruction of the iron-loaded oligomer

The mitochondrial protein frataxin plays a central role in mitochondrial iron homeostasis, and frataxin deficiency is responsible for Friedreich ataxia, a neurodegenerative and cardiac disease that affects 1 in 40000 children. Here we present a single-particle reconstruction from cryoelectron microscopic images of iron-loaded 24-subunit oligomeric frataxin particles at 13 and 17 angstrom resolutio

Isolation of hemicelluloses from barley husks

In this work, arabinoxylan, the primary hemicellulose in barley husks, was isolated from barley husks by steam explosion and ultrafiltration. Ultrafiltration and diafiltration were used to concentrate and to increase the purity of the product which was intended for use as an oxygen barrier film in food packaging. A composite fluoropolymer membrane with a nominal molecular mass cut-off of 10,000 g/

Ultrastructural characterization of dissociated embryonic ventral mesencephalic tissue treated with neuroprotectants.

Poor survival and differentiation of grafted dopamine neurons limits the application of clinical transplantation in Parkinson’s disease. The survival of grafted dopamine neurons is only improved by a factor of 2–3 by adding neuroprotectants during tissue preparation. We used dye exclusion cell viability and electron microscopy to investigate the effects of the caspase inhibitor ac-YVAD-cmk and the

Small-scale magnetic fields on late-type M-dwarfs

We performed kinematic studies of the evolution of small-scale magneticfields in the surface layers of M-dwarfs. We solved the inductionequation for a prescribed velocity field, magnetic Reynolds number ReM,and boundary conditions in a Cartesian box, representing a volumecomprising the optically thin stellar atmosphere and the uppermost partof the optically thick convective envelope. The velocity

An MC-SS platform for short-range communications in the Personal Network context

Wireless Personal Area Networks (WPAN) has gained interest in the last few years and several air interfaces have been proposed to cover WPAN applications. A Multi-Carrier Spread Spectrum (MC-SS) air interface specified to achieve 130 Mbps in typical WPAN channels, is presented in this paper. It operates in the 5.2 GHz ISM band and achieves a spectral efficiency of 3.25 b.s-1.Hz-1. Besides the robu

Theory based policy evaluation of 20 energy efficiency instruments

Realizing a 20% energy efficiency improvement in Europe by 2020 requires the introduction of good new energy efficiency policies as well as strengthening and enforcing the existing policies. This raises the question: what characterizes good and effective energy efficiency policies and their implementation? Systematic ex post evaluation of energy efficiency policies can reveal factors determining n

Removal of Nickel onto Alkali Treated Rice Bran

Different bases were used for the pretreatment of Rice bran biomass. Pretreatment with bases such as NaOH, Ca(OH)(2) and Al(OH)(3) were found to improve biosorption capacity. But in Rice bran, treatment with 0.5 M NaOH increased its nickel selective adsorption ability very much. The main binding site of nickel in NaOH treated cells is assumed to be carboxylic, hydroxyl, sulphate, phosphate and ami

Conformational disorder of conjugated polymers

Conformational disorder of conjugated polymers is an important issue to be understood and quantified. In this paper we present a new method to assess the chain conformation of conjugated polymers based on measurements of intrachain energy transfer. The chain conformation is modeled on the basis of monomer-monomer interactions, such as torsion, bending, and stretching of the connecting bond. The la

Minimization of immunosuppressive therapy after renal transplantation: Results of a randomized controlled trial

Modern immunosuppressive regimens reduce the acute rejection rate by combining a cornerstone immunosuppressant like tacrolimus or cyclosporine with adjunctive agents like corticosteroids, mycophenolate mofetil (MMF) or azathioprine, often associated with untoward side effects. A 6-month randomized study was conducted in 47 European centers. Triple therapy with tacrolimus (trough levels 5-15 ng/mL)

The effect of silver ions and chlorine on the survival of Staphylococcus aureus and Bacillus cereus in dishwater

This paper investigates the effect of chlorine and silver ion solutions on the survival of Bacillus cereus (vegetative phase) and Staphylococcus aureus in batch cultures, representing dishwater. Dishwater contains organic matter and bacteria and bacterial activities are partly reduced by high pH (11-12) and temperature (55-65 degrees C) in professional and domestic dishwashers. in manual dishwashi

The balance between sexual and asexual reproduction in plants living in variable environments

The balance between sexual and asexual propagule production is studied in an evolutionary model where plants produce the two kinds of propagules in genetically determined proportions. The male function of plants producing asexual propagules can be varied, and the sexual and asexual propagules carry different probabilities to turn into new reproductive individuals. These fitnesses may vary over yea

Benefits of Virtual Characters in Computer Based Learning Environments: Claims and Evidence

Pedagogical theory of today gives high priority to social components of learning. Within the field of computer supported learning there are many attempts to acknowledge this. One approach involves the addition of virtual characters to electronic learning environments. Such character enhanced systems are the focus of the present article. Firstly, a systematic overview is given of pedagogical benefi

Statistical Estimation and Interpretation of Trends in Water Quality Time Series

Three approaches to trend analysis of water quality time series are discussed: (1) seasonal model, with a test for trend based on ranks of observations, with observations assumed to be m dependent; (2) transfer function noise model, in which covariate series may be included by means of transfer functions, with the remaining noise modeled as a seasonal autoregressive moving average process; and (3)

Biomass and composition of understory vegetation and the forest floor carbon stock across Siberian larch and mountain birch chronosequences in Iceland

Changes in understory biomass, forest floor carbon (C) stock and vegetation composition were studied in six age-classes of Siberian larch (Larix sibirica) and two age-classes of native birch (Betula pubescens) in Iceland. The ground vegetation was less in the larch during the thicket stage and in the old-growth birch compared to a treeless pasture. Understory biomass was strongly related to canopy

Factors affecting attitudes towards medical abortion in Lithuania

Objective Surgical abortion in Lithuania is governed by a 1994 ministerial decree that made it legal for any woman 16 or older. This article seeks to determine the key demographic factors in Lithuanian attitudes towards medical abortion, which is currently not legal. Methods A random sample of the adult population was asked if they supported medical abortion. The dependent variable of attitude tow