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Phosphorus fractions in grassland soils

The partitioning of P among major chemical forms was studied in 110 non-fertilized, semi-natural grassland soils of southeastern Sweden, comprising a wide range of soil acidity and other chemical properties. The P fractions bound to Ca and Fe were closely related to soil acidity, expressed as pH-KCl, especially when calculated as % of the total pool of mineral P. The relationship was inversely lin

A decade of progress in understanding the structural basis of protein synthesis

The key reaction of protein synthesis, peptidyl transfer, is catalysed in all living organisms by the ribosome - an advanced and highly efficient molecular machine. During the last decade extensive X-ray crystallographic and NMR studies of the three-dimensional structure of ribosomal proteins, ribosomal RNA components and their complexes with ribosomal proteins, and of several translation factors

Effect of nedocromil sodium on non-adrenergic, non-cholinergic neural responses in guinea pig bronchi in vitro

OBJECTIVE: Nedocromil sodium (nedocromil) improves the clinical condition of asthmatic subjects but its mechanism of action is not fully understood. This study aimed to determine whether nedocromil alters the ability of contractile and relaxant non-adrenergic, non-cholinergic neural (NANC) responses to stabilise tone by inhibiting or potentiating these responses in bronchial smooth muscle and, if

Comparison of the chemical properties of iron and cobalt porphyrins and corrins.

Density functional calculations have been used to compare various geometric, electronic and functional properties of iron and cobalt porphyrin (Por) and corrin (Cor) species. The investigation is focussed on octahedral MII/III complexes (where M is the metal) with two axial imidazole ligands (as a model of b and c type cytochromes) or with one imidazole and one methyl ligand (as a model of methylc

The diffusion of water vapour through pulp and paper

The diffusion of water vapour through pulp and paper was investigated experimentally in a diffusion cell. The diffusion cell consisted of two chambers differing in relative humidity. Any given sample was placed as a barrier between the two chambers. Two pulp qualities and eleven paper grades were included in the investigation. The diffusivities measured ranged from 2.1-10(-8) m2/s to 5.4.10(-6) m2

Molecularly imprinted polymers in capillary electrochromatography: Recent developments and future trends.

The developments in molecularly imprinted polymer (MIP)-based capillary electrochromatography (CEC) achieved during the past years are reviewed in this article. The MIP is prepared using a templated polymerization reaction and results in a material with a high selectivity towards a predetermined target. The selectivity of the MIP is comparable to that of the biological antibodies, however, the MIP

Thin layers of GaInP, GaP and GaAsP in metalorganic vapour phase epitaxy-grown resonant tunnelling diodes

We have studied the epitaxial growth and electrical performance of Al-free, GaAs-based, resonant tunnelling diodes (RTDs) including thin barriers of GaInP, GO, or GaAsxP1-x. n-Type tunnelling diodes have been fabricated and the symmetry in the current-voltage (I-V) characteristics, as well as the peak-to-valley ratios, are found to be sensitive probes for the inter-face quality in the heterostruct

Seeing red: morph-specific contest success, and survival rates, in a colour-polymorphic agamid lizard

Red coloration in multicoloured or polymorphic species has been associated with dominance in a number of case studies, including probability of winning in human sports. However, it is not clear at what stage during ontogeny the association between red and the probability of winning contests occurs (or being perceived as more threatening by a contradistinct rival), for example, at conception, early

Quantification of myocardial hypoperfusion with 99m Tc-sestamibi in patients undergoing prolonged coronary artery balloon occlusion.

SUMMARY: Percutaneous transluminal coronary angioplasty provides an excellent opportunity to investigate the location and quantity of hypoperfusion during sudden complete occlusion of one of the major coronary arteries. Thirty-five patients referred for elective percutaneous transluminal coronary angioplasty were injected intravenously with 99mTc-sestamibi during balloon inflation. To visualize an

Anthropology, Social Theory and Politics. Axel Honneth's Theory of Recognition

The article presents and discusses Axel Honneth's theory of recognition as a specific constellation, i.e. as a theoretical endeavour spanning over and interrelating positions in the fields of anthropology, social theory, and politics. As essential components in this constellation is discerned an anthropology of recognition, a social philosophy of different forms of recognition, a morality of recog

Active and passive immunization for atherosclerosis

This review summarizes experimental findings that highlight the role of immune mechanisms in atherosclerosis and the potential atheroprotective effects of active or passive immunization strategies. Immunomodulation therapy appears to be feasible and effective, suggesting that a vaccine for atherosclerosis can be developed for clinical testing. Given the increasing number of patients with atheroscl

The fluorescence lidar technique for the remote sensing of photoautotrophic biodeteriogens in the outdoor cultural heritage: A decade of in situ experiments

Fluorescence lidar is a non-invasive, remote sensing technique that makes it possible to extend the application of the laser-induced fluorescence technique to the outdoor environment where uncontrolled, external conditions must be met. Although initially developed for the investigation of marine environment and vegetation, in the past decade this technique has been successfully applied to the fiel

Polycyclic aromatic hydrocarbon biodegradation by a subtropical white rot fungus in packed bed and suspended carrier bioreactor systems

Application of a biotreatment system utilising immobilised white rot fungi can become an alternative for treating water or effluent contaminated by organic pollutants such as polycyclic aromatic hydrocarbons (PAHs). The application of the packed bed and suspended carrier bioreactor systems for the degradation of PAHs in synthetic polluted media using a subtropical white rot fungal isolate DSPM95 w

Use of neural networks to improve quality control of interpretations in myocardial perfusion imaging

Background: The aim of this study was to explore the feasibility of using a technique based on artificial neural networks for quality assurance of image reporting. The networks were used to identify potentially suboptimal or erroneous interpretations of myocardial perfusion scintigrams (MPS). Methods: Reversible perfusion defects (ischaemia) in each of five myocardial regions, as interpreted by on

Contact-free measurements and numerical analyses of the strain distribution in the joint area of steel-to-timber dowel joints

Two different dowel-type joints of differing size were loaded in tension parallel to the grain. The strain distribution in the joint area was studied using a contact-free measurement system. The results were compared with those of numerical analysis. The measurement system was found to be a valuable complement to traditional measurement techniques and also to numerical analyses performed in parame

Dissociation of water on oxygen-covered Rh{111}

The adsorption of water and coadsorption with oxygen on Rh{111} under ultrahigh vacuum conditions was studied using synchrotron-based photoemission and photoabsorption spectroscopy. Water adsorbs intact on the clean surface at temperatures below 154 K. Irradiation with x-rays, however, induces fast dissociation and the formation of a mixed OH+H2O layer indicating that the partially dissociated lay

Proteomic variation is as large within as between strawberry varieties

in search for a strawberry (Fragaria ananassa) with low allergen content, we determined the proteomic variation within and between different varieties. Proteomics data were generated by DIGE and proteins identified with MALDI-MS/MS. The amount of the strawberry allergen Fra a 1 varied between different strawberry varieties (CV = 39%). The variation was at the same level, or even slightly larger, d

Allozyme diversity and genetic structure of marginal and central populations of Corylus avellana L. (Betulaceae) in Europe

Corylus avellana L. (hazel, Betulaceae) is a long-lived, widespread shrub in Europe, having its northern range margin in Fennoscandia and a postglacial history involving range-expansion from refugial areas in southern Europe. In this study, we tested for a relationship between marginality and low within-population genetic diversity by assessing patterns of variation at 14 putatively neutral allozy

Induces vasodilatation of rat mesenteric artery in vitro mainly by inhibiting receptor-mediated Ca2+-influx and Ca2+-release

The purpose of this study was to investigate the effect of atropine on peripheral vasodilation and the mechanisms involved. The isometric tension of rat mesenteric artery rings was recorded in vitro on a myograph. The results showed that atropine, at concentrations greater than 1 mu M, relaxed the noradrenalin (NA)-precontracted rat mesenteric artery in a concentration-dependent manner. Atropine-i