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Influence of defects on the lattice constant of GaMnAs

We study the influence of the major compensating defects As antisites and Mn interstitials known to occur in the GaMnAs ferromagnetic semiconductor on its structural properties. Our experimental results show that there is a balance between Mn interstitial and As antisite defects, leading to the reduced density of one type of defect upon increasing the density of the other defect. Significant diffe

Monte Carlo Simulation of Transmission Studies using a Planar Sources with a Parallel Collimator and a Line Source with a Fan-Beam Collimators

A knowledge of the distribution of the attenuation coefficient is generally required for a successful correction of attenuation in nonhomogeneous regions. This can be accomplished by performing transmission measurement with either parallel or fan-bean collimation. The Monte Carlo method makes it possible to fully evaluate the results of such a correction. This study shows results from such simulat

The relationship between different forms of human alpha-mannosidase

The tissue distribution and some properties of human alpha-mannosidase (alpha-D-mannoside mannohydrolase EC 3.2.1.24) have been studied. The acidic forms of the enzyme were fairly stable, whereas the neutral forms easily lost enzymic activity. The acidic forms were sensitive to neuraminidase but the neutral forms were unaffected. The experiments indicate that the acidic components are closely rela

Antibodies to factor VIIa in patients with haemophilia and high-responding inhibitors.

The haemostatic effect of by-passing agents such as activated prothrombin complex concentrates (aPCC) and recombinant factor VIIa is inadequate in some patients with severe haemophilia and high-responding inhibitors. Theoretically, this could be due to antibody reactivity to procoagulant proteins other than the deficient factor. To evaluate this hypothesis, immunoglobulin (Ig) fractions from six m

Demonstration of mitochondrial oestrogen receptor beta and oestrogen-induced attenuation of cytochrome c oxidase subunit I expression in human periodontal ligament cells.

OBJECTIVE: Periodontal ligament (PDL) cells express oestrogen receptor beta (ERbeta) protein, but cellular functions regulated by ERbeta in these cells have not been identified. In this study we determine if ERbeta is localised to mitochondria and if oestrogen regulates mitochondrial function in human PDL cells obtained from teeth extracted for orthodontic reasons. DESIGN: Subcellular distribution

Size dependent fragmentation of argon clusters in the soft x-ray ionization regime.

Photofragmentation of argon clusters of average size ranging from 10 up to 1000 atoms is studied using soft x-ray radiation below the 2p threshold and multicoincidence mass spectroscopy technique. For small clusters (N=10), ionization induces fast fragmentation with neutral emission imparting a large amount of energy. While the primary dissociation takes place on a picosecond time scale, the fragm

Detection of short lived radioisotopes as a fast diagnostic for intense laser-solid interactions

As a diagnostic of high-intensity laser interactions (> 10(19) W cm(-2)), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to meas

Combustion process in a biomass grate fired industry furnace: a CFD study

This paper presents a CFD investigation of the combustion process in a 50 MW grate fired furnace. The CFD results were compared with available experimental data at the furnace Outlet to validate the models for the volatile oxidation and NOx formation. The models were then used to predict the effect of a 'ECO' tube system on NOx emissions. It was shown that with an improved flow structure and air d

An atypical intra-platform environment and biota from the Silurian of Gotland, Sweden

A condensed shale from the middle Silurian of Gotland (Sweden) is herein described with regard to its biotic and environmental significance. The fauna is characterised by an overall low diversity and anomalous abundance patterns, notably a mass-occurrence of scolecodonts. Other elements include abundant chitinozoans, dendroid and graptoloid graptolites, conodonts, eurypterids, and the brachiopod L

Binding of adenosine to pendant phenylboronate groups of thermoresponsive copolymer: a quantitative study

Binding of adenosine to the thermosensitive copolymer of N-isopropylacrylamide and 3-(acrylamido)aminophenylboronic acid (82:18, m ($) over bar (n)=47000 g center dot mol(-1)) was studied by equilibrium dialysis at 22 degrees C and 37 degrees C, in a 0.1 m glycine buffer containing 0.1 m NaCl at pH 9.2. The copolymer exhibited a the phase transition temperature (T-p) of 26.5 degrees C under the ab

Transcriptional responses of Paxillus involutus and Betula pendula during formation of ectomycorrhizal root tissue

In order to obtain information on genes specifically expressed in the ectomycorrhizal symbiosis, 3,555 expressed sequence tags (ESTs) were analyzed from a cDNA library constructed from ectomycorrhiza formed between the basidiomycete Paxillus involutus and birch (Betula pendula). cDNA libraries from saprophytically growing fungus (3,964 ESTs) and from axenic plants (2,532 ESTs) were analyzed in par

Haem-delivery proteins in cytochrome c maturation System II

P>Cytochromes of the c-type function on the outer side of the cytoplasmic membrane in bacteria where they also are assembled from apo-cytochrome polypeptide and haem. Two distinctly different systems for cytochrome c maturation are found in bacteria. System I present in Escherichia coli has eight to nine different Ccm proteins. System II is found in Bacillus subtilis and comprises four proteins: C

Soda lime temperatures during low-flow sevoflurane anaesthesia and differences in dead-space.

BACKGROUND: Sevoflurane degrades during low-flow anaesthesia to compound A, and high carbon dioxide absorbent temperatures cause increased degradation. The purpose of this investigation was to determine if larger tidal volumes, without increasing alveolar ventilation, decrease the temperature in the carbon dioxide absorber during low- and minimal-flow sevoflurane anaesthesia. METHODS: Prospective,

Point prevalence of neurosis in the Lundby Study 1947-1997.

The objective of this article is to report and discuss the changing point prevalence rate of neurosis 1947-1997 in the Lundby cohort. The Lundby Study is a prospective longitudinal study of a geographically defined total population in the south of Sweden. Field investigations were performed in 1947, 1957, 1972 and in 1997, with psychiatrists interviewing the probands in a semi-structured way. Addi

Transient wave propagation in composite media: Green's functions approach

A generalized Green's function technique for wave propagation of transient fields in one-dimensional media is developed. The medium is partitioned into an arbitrary number of subslabs for which Green operators that map the incident field to the internal fields are defined. Relations between the Green operators for the entire medium and the Green operators for the subslabs are derived. The techniqu