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1.
The aim of the study was to discover determinants of the onset of life threatening ventricular tachyarrhythmia. 102 patients with acute myocardial infarction and 32 patients with postinfarction cardiosclerosis were examined. The data gained at programmed ventricular stimulation, high resolution ECG, Holter ECG monitoring, spectral analysis of cardiac rhythm variability and two-dimension echocardiography proved the importance of early postinfarction left ventricular dilatation in the onset of electrical cardiac instability, establishment of anatomic substrate of monomorphic ventricular tachycardias, low variability of cardiac rhythm. The findings evidence that MI patients with late ventricular potentials and end-diastolic left ventricular index above 100 ml/m2 in subacute period may be considered as a group of high risk in need of individual approach and further therapy. The discovered lowering of informative value of non-invasive methods in patients late after MI dictates the necessity of new approaches to detection of electrophysiological disturbances and sudden death risk in registration of postinfarction dilatation of the heart.  相似文献   
2.
Multimedia Tools and Applications - The copyright protection of three-dimensional (3D) content is a matter of interest in artistic and creative works due to the rights of the holder for the...  相似文献   
3.
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable.  相似文献   
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5.
We have studied a laser system with quick electronic tuning of the spectrum shape and continuous distribution. The proposed method is based on separate control of phase and amplitude spatial distributions of resonator transmittance. Evolution of the spectral function of the diffractively coupled dispersive resonators and the model for the formation of the resonator with the spectral function given by its moments are studied theoretically. The synthesis of continuous spectra is investigated experimentally in the laser with a novel control element including a spatial acousto-optic modulator and a tunable lens telescope.  相似文献   
6.
In feature-oriented programming (FOP) a programmer decomposes a program in terms of features. Ideally, features are implemented modularly so that they can be developed in isolation. Access control mechanisms in the form of access or visibility modifiers are an important ingredient to attain feature modularity as they allow programmers to hide and expose internal details of a module’s implementation. But developers of contemporary feature-oriented languages have not considered access control mechanisms so far. The absence of a well-defined access control model for FOP breaks encapsulation of feature code and leads to unexpected program behaviors and inadvertent type errors. We raise awareness of this problem, propose three feature-oriented access modifiers, and present a corresponding access modifier model. We offer an implementation of the model on the basis of a fully-fledged feature-oriented compiler. Finally, by analyzing ten feature-oriented programs, we explore the potential of feature-oriented modifiers in FOP.  相似文献   
7.
The method of small-angle neutron scattering has been used to investigate the samples of pure nickel before and after irradiation with fast neutron fluences of Φ = 1018, 1019, and 1020 cm?2 (E n ≥ 0.1 MeV). It has been found that the substructure of the samples consists of vacancy clusters with two characteristic sizes of 2.5–4 and ~7 nm. The sizes of precipitates weakly depend on fast neutron fluence. The magnitude of their density is on the order of 1022 and 1019 m?3, respectively, and increases by three to ten times as the fluence grows.  相似文献   
8.
Nd2 ? x Ca x CoO4 ± δ-based materials demonstrated high effectiveness in partial methane oxidation into synthesis gas with almost 100% selectivity. It has been determined that Nd2 ? x Ca x CoO4 ± δ materials synthesized via the solid-state or cryochemical methods are single-phase in the range of 0.6 ≤ x ≤ 1 at a synthesis temperatures of 1100–1200°C. Synthesis at t ≤ 1100°C allows to prepare solid solutions in the range of 0.9 < x < 1.05.  相似文献   
9.
This paper addresses reliable and efficient calculation of the mode of a multivariate sample, which is a classical fusion function. In particular, we focus on the inputs given on the unit simplex, when aggregating elements of Atanassov intuitionistic fuzzy sets, interval-valued fuzzy sets and their extensions, as well as compositional data. We outline the use of a specially designed 2-additive fuzzy measures and the Choquet integral for the purposes of reducing computational complexity in higher dimensions. We present computational analysis and benchmark four different methods of density-based mode estimation.  相似文献   
10.
Journal of Communications Technology and Electronics - A modified resonator method for determining the complex permittivity of materials based on the theory of small perturbations where a resonator...  相似文献   
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