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Vanadia was deposited on TiO2, ZrO2, HfO2, Nb2O5, and Ta2O5 supports using impregnation with either an oxalic acid solution of NH4VO3 or a solution of vanadyl acetylacetonate in ethanol. Prepared samples, with a nominal vanadia content in the range 0.5–2 monolayers, were characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman and infrared spectroscopy, and were us

We describe the qualitative dynamics and bifurcation set for a laser with injected signal for small cavity detunings. The main organizing center is the Hopf-saddle-node bifurcation from where a secondary Hopf bifurcation of a periodic orbit originates. We show that the laser's stable cw solution existing for low injections, also suffers a secondary Hopf bifurcation. The resonance structure of both

Lifetimes of fine-structure levels in 2s2p3p D-4 and 2s2p3d F-4(o) quartets are calculated in the boron isoelectronic sequence, for C II to F V, using a multiconfiguration Hartree-Fock approach. These quartets are known from earlier experimental and theoretical studies to have different lifetimes for different J-levels, owing to spin-induced transitions, mainly to doublet states in 2s(2)2p and 2s2

Background and aims: Chronic idiopathic intestinal pseudo-obstruction (CIIP) is a severe motility disorder associated with significant morbidity. Several histopathological ( neuropathic and myopathic) phenotypes have been described but only a single adult with jejunal smooth ( circular) muscle alpha-actin deficiency. We present a prospective multinational case series investigating smooth muscle al

In a long-term prospective study, 39 preterm children born before 35 completed weeks of gestation and 23 full-term children were followed up at 4, 9 and 19 years of age. Psychometric evaluation of the cognitive development at 4 years of age showed that the preterms fell within the normal range, although their performance was inferior to that of the full-terms. This difference between the groups wa

An approach to teaching calorimetry is offered through practical, versatile undergraduate experiments using an isothermal heat conduction calorimeter, which measures a variety of heat changes--enthalpies of phase changes, hydration, dissolution, adsorption and desorption, and reaction--as well as the metabolic rate of living organisms. Isothermal heat-conduction calorimetry is contrasted with adia

Polymeric catalysts to be applied in the Diels-Alder cycloaddition of hexachlorocyclopentadiene and maleic acid have been prepared via molecular imprinting with template molecules immobilized on silica particles. These enzyme mimicking polymers exhibit specific catalytic effects compared to non-imprinted control polymers or polymer-free solutions. It could be demonstrated that the activity of the

Biogas is a renewable, high-quality fuel, currently produced at more than 200 locations in Sweden. The present production is some 5 PJ/year but the potential is approximately 10 times higher. Biogas can be produced from a wide range of raw materials, from organic waste to dedicated energy crops, and can be utilised for various energy services such as heat, combined heat and power or as a vehicle f

Concerted activation of different voltage-gated Ca2+ channel isoforms may determine the kinetics of insulin release from pancreatic islets. Here we have elucidated the role of R-type CaV2.3 channels in that process. A 20% reduction in glucose-evoked insulin secretion was observed in CaV2.3-knockout (CaV2.3–/–) islets, close to the 17% inhibition by the R-type blocker SNX482 but much less than the

OBJECTIVE: The principal aim of the study was to estimate the level of exposure to organic solvents of graffiti removers, and to identify the chemicals used in different cleaning agents. A secondary objective was to inform about the toxicity of various products and to optimise working procedures. METHODS: Exposure to organic solvents was determined by active air sampling and biological monitoring

Current internal radiation dosimetry models for the small intestine, and for most walled organs, lack the ability to account for the activity uptake in the intestinal wall. In existing models the cross-dose from nearby loops of the small intestine is not taken into consideration. The aim of this investigation was to develop a general model for calculating the absorbed dose to the radiation-sensiti

Ultra-fast substitution of chloride for bromide, iodide, azide and thiocyanate trans to ethene in Zeise's anion, [PtCl3(C2H4)](-), 1, has been investigated in methanol solvent by use of cryo temperature diode array stopped-flow spectrophotometry. Reactions follow the usual two-term rate law for square-planar substitutions, k(obs)=k(1)+k(2)[Y] (where k(1)=k(MeOH) [MeOH]), with k(1)=118+/-10 s(-1) a

When skin specimens are exposed in vitro to L-dopa and catecholamines these substances accumulate in the Langerhans cells where they can be visualized with the histofluorescence method of Falck and Hillarp. Some methodological aspects are discussed and a preliminary study of Langerhans cells in contact allergy is reported.