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We have studied a rare-earth-doped crystal, Pr3+:La-2(WO4)(3), which exhibits a high magnetic-moment density. Although the latter favors rare-earth dephasing, a nuclear-spin coherence lifetime of 250 mu s has been observed, as well as electromagnetically induced transparency (EIT). This suggests that a broad range of materials could be considered for quantum information applications such as quantu

Catalysts belonging to the Sb-V-O system were prepared with various Sb/V ratios and were used for propane ammoxidation to acrylonitrile. XRD patterns of freshly prepared samples show those with excess vanadia to consist of V2O5 and SbVO4, while SbVO4 and α-Sb2O4 are constituents in the samples with a Sb/V ratio above unity. High rate and selectivity for propylene formation at low conversion are ch

Triptans are agonists at 5-HT1B and 5-HT1D (where 5-HT is 5-hydroxytryptamine; serotonin) receptors and cause vasoconstriction of isolated blood vessels. The aim of the present study was to determine vasoconstrictor potency (EC50) of triptans in human coronary and cerebral arteries and to examine whether there was any relationship with the maximal plasma concentrations (Cmax; nM) of the drugs achi

To evaluate the potential use of tree-ring data as a proxy for fire activity at the scale of a large boreal region, we analyzed a set of regional tree-ring chronologies of Siberian larch (Larix sibirica L.), a spatially implicit annual fire record, and monthly climate data for the Komi Republic for the period 1950-1990. In most years, annually burned area was below 0.001% of the republic's foreste

A model for a special configuration in triaxial odd-odd nuclei is constructed which exhibits degenerate chiral bands with a sizable rotation, a manifestation of dynamical spontaneous symmetry breaking. A quantum number obtained from the invariance of the model Hamiltonian, which characterizes observable states, is given and selection rules for electromagnetic transition probabilities in chiral ban

A 120 kHz echo sounder, with two split-beam transducers, was used horizontally to monitor the behaviour of 0+ roach Rutilus rutilis, from June to August, in field enclosures. 0+ roach outside the vegetated area of the enclosures were registered both as schools and as single swimming fish. Combining echo counting and tracking with direct observation of echograms, an estimate of relative abundance o

In this paper propagation of transient electromagnetic waves in a reciprocal bi-isotropic medium is presented. The constitutive relations are convolution integrals with two susceptibility kernels that model the medium. The propagation problem is solved by the introduction of a wave-splitting technique. This wave-splitting is used to solve the propagation problem using either an imbedding approach

1. I tested the hypothesis that the potential for non-lethal effects of predators are more important for overall performance of the fast-growing exotic signal crayfish (Pacifastacus leniusculus Dana) than for the slower growing native noble crayfish (Astacus astacus L.). I further tested if omnivorous crayfish switched to feed on less risky food sources in the presence of predators, a behaviour th

Cosmological investigations, using high-redshift quasi-stellar object (QSO) absorption spectra, of possible variations of the fine-structure constant (alpha) require very accurate laboratory wavelengths for a number of resonance transitions from several different species. A change in alpha could be detected as a shift in the wavelengths of atomic transitions in the QSO systems and to accurately de

IgG subclasses of glutamic acid decarboxylase (GAD(65)) antibodies (GADA) may reflect the immunological state in the pancreas of GADA-positive patients with autoimmune diabetes. The use of biotin-conjugated antibodies and streptavidin Sepharose are used commonly in immunoprecipitation assays (IPA) based on (125)I- or (35)S-labelled antigens to capture IgG subclasses directed against IA-2 or GAD(65

Background: Many strategies are currently being pursued in order to generate mature dendritic cells (DC) to be used for immunotherapy. A potent anti-tumour influence by extracorporeal photopheresis has been documented for cutaneous T-cell lymphoma, and a major mechanism of action has been suggested to be generation of DC presenting tumour antigens. Purpose: To determine the potential of a simple c

Gastrointestinal motor dysfunction persists in a large number of children subjected to surgical treatment for Hirschsprung's disease, indicating abnormalities in the remaining intestine. The aim of the study was to detect possible alterations in frequency and topographic distribution of enteric neurons and interstitial cells of Cajal in an experimental model (the lethal spotted mouse displaying a

The paediatric care of children with haemophilia in developed countries should focus on the health of the child, not on the disorder. Gene therapy offers the hope of an ultimate 'cure' for the disorder, but until this is a viable proposition, patients should be given more control over their treatment, and the focus should be on 'self-monitored and self-adjusted' prophylaxis. New instruments for me

The thickening effect of a hydrophobically modified polymer in an aqueous solution is dependent on intermolecular hydrophobic associations, and if the polymer concentration is significantly above the overlap concentration also on chain entanglements. In this investigation we have added different cyclodextrins (CD) in order to decouple hydrophobic polymer-polymer associations via inclusion complex

Methods that combine efficient solubilization with enrichment of proteins and intact protein complexes are of central interest in current membrane proteomics. We have developed methods based on nondenaturing detergent extraction of yeast mitochondrial membrane proteins followed by enrichment of hydrophobic proteins in aqueous two-phase system. Combining the zwitterionic detergent Zwittergent 3-10

The variations in atmospheric radiocarbon (C-14) concentration during the last 50 000 years can be attributed to changes in the C-14 production rate (due to changes in solar activity, the geomagnetic field and/or interstellar galactic cosmic ray flux) and to changes in the global carbon cycle. The relative contributions of these processes is the subject of current debate. Although the discrepancie

We report on a new survey of metallicities, ages, and Galactic orbitsfor a complete, magnitude-limited, and kinematically unbiased all-skysample of 16682 nearby F- and G-dwarfs. Our~63000 new, accurate radialvelocities for nearly 13500 of the stars, combined with Hipparcosparallaxes and Tycho-2 proper motions, complete the kinematic data for14139 stars and allow us to identify most of the binary s