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991.
Hanć A Komorowicz I Iskra M Majewski W Barałkiewicz D 《Analytical and bioanalytical chemistry》2011,399(9):3221-3231
The study was aimed to evaluate the influence of the vascular disease, atherosclerotic obliterans (AO), on the location and
concentration of elements in the arterial wall and serum. Use of a modern method for studying element’s concentration and
distribution in samples of clinical material, i.e. laser ablation inductively coupled plasma mass spectrometry, is presented.
Elements are not equally distributed between the inner (intima) and the outer (media + adventitia) layer of the arterial wall.
Among the studied elements, calcium was found to have an unquestionable role in the calcification of the wall. Increased concentration
of calcium found in the inner part of the atherosclerotic arterial wall and in the plaque, as compared to the control arterial
wall samples, demonstrates the unquestionable role of this element in the calcification of the wall observed in AO. Applied
chemometric methods were useful for demonstrating the differences in the element’s concentration in blood serum and the arterial
wall samples between AO and the control group. 相似文献
992.
In a series of papers, Green’s relations on the additive and multiplicative reducts of a semiring proved to be a very useful
tool in the study of semirings. However, in the vast majority of cases, Green’s relations are not congruences, and we show
that in such cases it is much more convenient to use the congruence openings of Green’s relations, instead of the Green’s
relations themselves. By means of these congruence openings we define and study several very interesting operators on the
lattices of varieties of semirings and additively idempotent semirings, and, in particular, we establish order embeddings
of the lattice of varieties of additively idempotent semirings into the direct products of the lattices of open (resp. closed)
varieties with respect to two opening (resp. closure) operators on this lattice that we introduced. 相似文献
993.
We consider the three-dimensional motion of a self-propelled deformable structure into a viscous incompressible fluid. The
deformation of the solid is given whereas its position is unknown. Such a system could model the propulsion of fish-like swimmers.
The equations of motion of the fluid are the Navier-Stokes equations and the equations for the structure are deduced from
Newton’s laws. The corresponding system is a free boundary problem and the main result of the paper is the existence of weak
solutions for this problem. 相似文献
994.
Vladimir Pavlović 《Acta Mathematica Hungarica》2011,131(3):295-306
We identify continuous real-valued functions on a Tychonoff space X with their (closed) graphs thus allowing for C(X) to naturally inherit the lower Vietoris topology from the ambient hyperspace. We then calculate a bitopological version of tightness using the weak Lindelöf numbers of finite powers of X. We also characterize bitopological versions of countable fan and strong fan tightness of the point-open topology with respect to the lower Vietoris topology on C(X) in terms of suitable covering properties of the powers X n formulated using the language of S 1 and S fin selection principles. 相似文献
995.
Snežana Č. Živković-Zlatanović Dragan S. Djordjević Robin E. Harte 《Integral Equations and Operator Theory》2011,69(3):347-363
We consider left and right Browder operators, left and right Fredholm operators, spectra related with these operators, and
various operator quantities. 相似文献
996.
997.
Various Meir–Keeler-type conditions for mappings acting in abstract metric spaces are presented and their connections are discussed. Results about associated symmetric spaces, obtained in [S. Radenovi?, Z. Kadelburg, Quasi-contractions on symmetric and cone symmetric spaces, Banach J. Math. Anal. 5 (2011), 38–50] are used to show that the regularity condition for the underlying cone can be dropped in some fixed point results that have appeared recently. 相似文献
998.
Dejan Brkić 《Applied Mathematics Letters》2011,24(8):1379-1383
999.
Predrag Tanović 《Mathematical Logic Quarterly》2011,57(3):256-260
We prove that every type of finite Cantor‐Bendixson rank over a model of a first‐order theory without the strict order property is definable and has a unique nonforking extension to a global type. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
1000.
For one of the most common network motifs, an inhibitory neuron pair, we perform an extensive study of burst synchronization and the related phenomena applying the model of Rulkov maps coupled via delayed synapses. Instigated by the phase-plane analysis, that has the neuron switching between the noninteracting and the interacting map, it is demonstrated how the system evolution may be interpreted by means of the dynamical configurations of the motif, each represented by an extracted subgraph. Under the variation of the synaptic parameters, the probability of finding synchronized neurons in a given configuration is seen to reflect the way in which the anti-phase synchronization is eventually superseded by the synchronization in phase. Such an approach also provides a novel insight into regularization, characterizing the neuron bursting in either of these regimes. Looking into correlation of the two neurons’ bursting cycles we acquire a deeper understanding of the more sophisticated mechanisms by which the regularity in the time series is maintained. Further, it is examined whether introducing heterogeneity in the neuron or the synaptic parameters may prove advantageous over the homogeneous case with respect to burst synchronization. 相似文献