Prevalence of artificial hip implants and use of health services by recipients

Intraneural injection of 10-20 x 10(6) viable Mycobacterium leprae into the sciatic nerve of normal, unsensitized, Swiss white mice gives rise to a tuberculoid type of granulomatous response in 2 weeks. The same dose of viable M. leprae when injected into the sciatic nerves of unsensitized immunosuppressed mice (T200 x 5R) elicited a macrophage response. When macrophages were systemically immobilized using an intraperitoneal injection of silica quartz dust in normal mice, the lesion produced was of the lepromatous type, suggesting a role for the macrophage in the induction of the tuberculoid type of granulomatous response. In all of these in situ experiments, M. leprae failed to enter the Schwann cells.     

Kinetic and spectral aspects in chemiluminescence system Eu(III)/HCO3/H2O2

Chemiluminescence (CL) of the systems containing Eu₂⁺ or HCO₃⁻ ions and hydrogen peroxide was studied. The kinetic curves and CL emission spectra of the systems were discussed. The emission spectrum of the system containing carbonates revealed two emission maxima: the first directly after initiation of the reaction by hydrogen peroxide and the second in several seconds after the first. On the basis of the characteristic bands in the CL spectrum the emitters in the system Eu₂⁺/HCO₃⁻/H₂O₂ were identified as: excited Eu³⁺ ions and excited products of carbonate decomposition. The emission bands for λ=600 and 420 nm appeared in a time distance of a few ten seconds.     

Novel lanthanide salicylaldimine complexes with unusual coordination mode

The one-step metal promoted reaction between salicylaldehyde and 4-methyl-1,3-phenylenediamine in the presence of lanthanum(III) or gadolinium(III) nitrate yields new salicylaldimine complexes containing N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine as a result of the [2 + 1] Schiff base condensation. The crystal structure of the gadolinium complex reveals a dinuclear species with four unionized ligands coordinating in the monodentate and bridging bidentate fashion, using exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in coordination. The coordination number of nine is achieved by involving three bidentate nitrate counterions in the coordination sphere.     

Self-optimizing generalized adaptive notch filters — comparison of three optimization strategies

The paper provides comparison of three different approaches to on-line tuning of generalized adaptive notch filters (GANFs) — the algorithms used for identification/tracking of quasi-periodically varying dynamic systems. Tuning is needed to adjust adaptation gains, which control tracking performance of GANF algorithms, to the unknown and/or time time-varying rate of system nonstationarity. Two out of three compared approaches are classical solutions — the first one incorporates sequential optimization of adaptation gains while the second one is based on the concept of parallel estimation. The main contribution of the paper is that it suggests the third way — it shows that the best results can be achieved when both approaches mentioned above are combined in a judicious way. Such joint sequential/parallel optimization preserves advantages of both treatments: adaptiveness (sequential approach) and robustness to abrupt changes (parallel approach). Additionally the paper shows how, using the concept of surrogate outputs, one can extend the proposed single-frequency algorithm to the multiple frequencies case, without falling into the complexity trap known as the “curse of dimensionality”.     

Influence of megaplastic deformation on the structure and hardness of Al–Cu–Mg alloy after aging

Methods of electron microscopy and X-ray diffraction have been used to investigate structural and phase transformations in the aluminum alloy of grade A2024 (Al–4.5 Cu–1.37 Mg–0.61 Mn–0.07 Si–0.27 Fe–0.02 Zn–0.02 Ti (wt %)) after aging and deformation by shear under high quasi-static pressure. It has been shown that the combination of two-stage aging with megaplastic deformation leads to the refinement of the structure to a nanolevel and to strengthening of the alloy (to an increase in the microhardness to 3000 MPa). The values of true deformation at which the deformation-induced dissolution of the particles of the strengthening S phase occurs have been determined.     

Electron spin resonance of FeVO4

We report on electron spin resonance (ESR) investigations of a FeVO₄ single crystal. Temperature and angular dependences of ESR resonance positions were measured and calculated in temperature range of 35–100 K. The spectra show rich angular dependences of the linewidth, the shape and the resonance field. They consist of a single broad line with asymmetric distortion. Due to the low symmetry of the crystal lattice this distortion can be explained by taking into account the influence of non diagonal dynamic susceptibility.     

Spectral analysis in ultraweak emissions of chemi- and electrochemiluminescence systems

Investigation of ultraweak emissions in the processes of chemiluminescence, CL, and electrochemiluminesce, ECL, requires special techniques of their recording and spectral analysis. From among the hitherto proposed methods of detection of the emission spectra of these processes, that of the cut-off filter was most sensitive. The usefulness of this method in interpretation of the CL and ECL systems of the quantum yields in the range 1×10⁻⁹−1×10⁻¹¹ containing ions and complexes of Eu(III), Tb(III) and Dy(III) was shown. Exceptional character of the emission bands of lanthanide ions, being a result of the f-f electron transitions and in particular their low FWHM, permitted the application of the cut-off filter method to their analysis. The results obtained for CL and ECL on the basis of analysis of ultraweak emission proved to be successful in analytical applications. The systems containing Eu(III) ions hydrated or complexed with organic ligands enabled inferring changes in the coordination sphere of the ions.