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161.
162.
A. N. Korolevich N. S. Dubina S. I. Vecherinskii M. S. Belsley 《Journal of Applied Spectroscopy》2004,71(4):572-579
The influence of low-intensity laser radiation (LLR) on the rheological characteristics of human blood has been investigated. The results of the investigation of the blood velocity in the human skin capillaries, the erythrocyte aggregation time, and the spectral width of scattering intensity fluctuations depending on the irradiation time are presented. It has been shown that laser irradiation leads to a decrease in the degree of aggregation of erythrocytes and, accordingly, to an increase in the velocity of blood microcirculation, which can be used for laser therapy and diagnostics and treatment of cardiovascular diseases (CVD). To explain the results obtained, a method of the LLR–biotissue interaction is proposed. 相似文献
163.
A new technique for the identification of ultrasonic flaw signals using deconvolution 总被引:1,自引:0,他引:1
The identification of ultrasonic flaw signals is a difficult task in the angle beam ultrasonic testing of welded joints due to the presence of non-relevant signals from the geometric reflectors such as weld-roots and counter-bores. This paper describes a new approach to identify ultrasonic flaw signals in such a problematic situation. A similarity function is defined as the deconvolution of a target signal by a reference signal. The similarity functions for the same type of flaws/references are symmetric bandlimited impulse-like patterns with larger amplitudes while those for different types of flaws/references are asymmetrical broad patterns with relatively smaller amplitudes. Therefore, ultrasonic signals could be identified by the pattern of the similarity function. In the initial experiments, the proposed technique showed great potential for identifying ultrasonic flaw signals in the inspection of weld joints. 相似文献
164.
Fré dé ric Bayart 《Proceedings of the American Mathematical Society》2003,131(6):1789-1791
We study the composition operators which are similar to an isometry on the classical Hardy space .
165.
Yong Jung Kim 《Journal of Differential Equations》2003,192(1):202-224
The goal of this article is to develop a new technique to obtain better asymptotic estimates for scalar conservation laws. General convex flux, f″(u)?0, is considered with an assumption . We show that, under suitable conditions on the initial value, its solution converges to an N-wave in L1 norm with the optimal convergence order of O(1/t). The technique we use in this article is to enclose the solution with two rarefaction waves. We also show a uniform convergence order in the sense of graphs. A numerical example of this phenomenon is included. 相似文献
166.
G. Oppenheim M. Ould Haye M.-C. Viano 《Statistical Inference for Stochastic Processes》2000,3(1-2):53-68
This review is devoted to stationary discrete time second order processes whose covariance asymptotically behaves like an hyperbolically damped oscillating sequence. We present the two main ways of generating parametric models of this type. Then we gather some results concerning the influence of seasonality on the classical limit theorems. Finally, we present a simulation method which we use to try a semi parametric estimation procedure adapted from the non seasonal situation. 相似文献
167.
Noboru Mizushima 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2007,83(2):39-46
Autophagy is in principle a non-selective degradation system within cells, which is conserved in all eukaryotic cells. Autophagy is usually suppressed at low levels but can be upregulated during periods of nutrient starvation, which facilitates cell survival. In addition to this fundamental role, basal autophagy was recently revealed to be important for constitutive turnover of intracellular proteins and organelles. Autophagy has been considered to be involved also in presentation of endogenous antigens, degradation of invasive bacteria, tumor suppression, cell death and development. This review will discuss the biological significance of autophagy, particularly focusing on its implications in protein metabolism in mammals. 相似文献
168.
169.
A series of novel derivatives of 4, 5, 6, 7-tetrahydrothieno [3,2-c] pyridine were synthesized and structurally characterized by 1H NMR and MS. Their in vivo anti-platelet aggregation activities were evaluated. A 3D-QSAR was performed using the CoMFA and the CoMSIA. This model provided useful guidelines for novel anti-platelet thienopyridines design. 相似文献
170.
For stochastic control problems with mixed state-control constraints, we develop a dynamics aggregation method which replaces the stochastic differential or difference equation with a simpler constraint. Solutions of such simplified problems are used to construct a sequence of approximations to the original problem. Convergence properties of the method for both discrete-time and continuous-time models are analyzed in detail. 相似文献