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91.
Exposing experimental animals or human volunteers to UVA II (320-340 nm) radiation after immunization suppresses immunologic memory and the elicitation of delayed-in-time hypersensitivity reactions. Previous studies indicated that the mechanisms underlying UVA-induced immune suppression are similar to those described for UVB-induced immune suppression, i.e. transferred by T regulatory cells, overcome by repairing DNA damage, neutralizing interleukin (IL)-10 activity, or injecting recombinant IL-12. Here we continued our examination of the mechanisms involved in UVA II-induced suppression. Antibodies to cis-urocanic acid blocked UVA-induced immune suppression. Treating UVA-irradiated mice with histamine receptor antagonists, calcitonin gene-related peptide (CGRP) receptor antagonists or platelet activating factor receptor antagonists blocked immune suppression in UVA-irradiated mice. In light of the fact that cis-urocanic acid and CGRP target mast cells, which can then release platelet activating factor and histamine, we measured UVA-induced immune suppression in mast cell-deficient mice. No immune suppression was noted in UVA-irradiated mast cell-deficient mice. These findings indicate that exposure to UVA II activates many of the same immune regulatory factors activated by UVB to induce immune suppression. Moreover, they indicate that mast cells play a critical role in UVA-induced suppression of secondary immune reactions. 相似文献
92.
Polina Khrennikova Emmanuel Haven Andrei Khrennikov 《International Journal of Theoretical Physics》2014,53(4):1346-1360
The Gorini-Kossakowski-Sudarshan-Lindblad equation allows us to model the process of decision making in US elections. The crucial point we attempt to make is that the voter’s mental state can be represented as a superposition of two possible choices for either republicans or democrats. However, reality dictates a more complicated situation: typically a voter participates in two elections, i.e. the congress and the presidential elections. In both elections the voter has to decide between two choices. This very feature of the US election system requires that the mental state is represented by a 2-qubit state corresponding to the superposition of 4 different choices. The main issue is to describe the dynamics of the voters’ mental states taking into account the mental and political environment. What is novel in this paper is that we apply the theory of open quantum systems to social science. The quantum master equation describes the resolution of uncertainty (represented in the form of superposition) to a definite choice. 相似文献
93.
Convergence Rate of Galerkin Method for a Certain Class of Nonlinear Operator-Differential Equations
Polina Vinogradova 《Numerical Functional Analysis & Optimization》2013,34(3):339-365
In this article, we study a Galerkin method for a nonstationary operator equation with a leading self-adjoint operator A(t) and a subordinate nonlinear operator F. The existence of the strong solutions of the Cauchy problem for differential and approximate equations are proved. New error estimates for the approximate solutions and their derivatives are obtained. The developed method is applied to an initial boundary value problem for a partial differential equation of parabolic type. 相似文献
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95.
Alan J. Jones Clifford C. Leznoff Polina I. Svirskaya 《Magnetic resonance in chemistry : MRC》1982,18(4):236-240
The 13C NMR spectra of a wide variety of organic substrates bound to 2% cross-linked polystyrenes may be obtained routinely, provided the resins can be sufficiently swollen. The 13C chemical shifts of polymer-bound trityl alcohol, polymer-bound monotrityl ethers of the symmertrical diols HO (CH2)nOH (n=2, 4, 6, 7, 9 and 10), and some related intermediates in the solid phase synthesis of insect pheromones are presented. 13C shift additivity correlations, differing little from those in free trityl ethers, are drawn. 相似文献
96.
M. K. Kurbanaliev A. A. Tager B. N. Narzullaev N. S. Rasulov I. K. Dustov V. E. Dreval' A. A. Anikeeva 《Mechanics of Composite Materials》1973,9(2):320-322
The authors examine the influence of the nature of the solvent on the time dependence of the strengths of films obtained from solutions of cellulose acetate in various solvents. They found that the durability of the films depends on the nature of the solvent. They have established that as the thermodynamic affinity of the solvent in the film-forming solutions gets worse, the durability of the films passes through a maximum; the nature of the solvent influences the parameter in the equation for the durability, which is responsible for changes in the structure of the polymer.V. I. Lenin Tadzhik State University, Dushanbe. A. M. Gor'kii Ural State University, Sverdlovsk. Translated from Mekhanika Polimerov, No. 2, pp. 360–362, March–April, 1974. 相似文献
97.
E. I. Zhmurikov A. I. Romanenko P. V. Logachev K. V. Gubin O. B. Anikeeva Tecchio Luigi 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(1):60-63
The conductivity of graphite composite samples MPG-6 and MPG-7 has been measured before and after 1.4 MeV electron irradiation and heating by alternating current up to temperatures higher than 2500°C, causing the fracture of the samples. It has been shown that both heating and electron irradiation result in a shift of the temperature dependence of the conductivity of the samples, namely, in an increase in conductivity. The measurements of the relative magnetoresistance at helium temperature in fields of ±1.15 T have shown that the imperfection of the macrostructure increases. The noticeable changes in the x-ray phase diagram do not observed up to the fracture of the samples. All the obtained data make it possible to suppose that the ultimate strength and the lifetime of graphite composites are limited by intercrystalline or grain boundaries. 相似文献
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100.
Saibabu Polina V. P. Rama Kishore Putta Raghuram Gujjarappa Prasad Pralhad Pujar Chandi C. Malakar 《Journal of heterocyclic chemistry》2021,58(4):1029-1033
An efficient and mild protocol was realized using 1,2-diazoles and related heterocycles with cyclic and acyclic enones in presence of T3P (2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide) toward the regioselective formation of N-cycloalkyl heterocycles at room temperature. The developed reaction conditions showcased good selectivity over a wide range of 1,2-diazoles and enones by delivering N-cycloalkyl heterocycles in excellent yields. 相似文献