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991.
The problem of electing a leader in a dynamic ring in which processors are permitted to fail and recover during election is discussed. It is shown that &thetas;(n log n +k r) messages, counting only messages sent by functional processors, are necessary and sufficient for dynamic ring election, where k r is the number of processor recoveries experienced 相似文献
992.
Je‐Ruei Liu Sheng‐Yao Wang Ming‐Ju Chen Pei‐Ying Yueh Chin‐Wen Lin 《Journal of the science of food and agriculture》2006,86(15):2527-2533
Food allergy is now recognized as a worldwide problem, and like other atopic disorders its incidence appears to be increasing. Kefir is reported to possess the ability to reduce intestinal permeation of food antigens; however, no experimental study has clearly evaluated the relationships between kefir consumption, allergen‐specific IgE response, and intestinal microflora. The aim of this study was to evaluate the effect of oral consumption of milk kefir and soymilk kefir on in vivo IgE and IgG1 production induced by ovalbumin (OVA) in mice. The effects of kefir administration on the murine intestinal microflora were also examined. Oral administration of milk kefir and soymilk kefir for 28 days significantly increased the fecal populations of bifidobacteria and lactobacilli, while it significantly decreased those of Clostridium perfringens. Milk kefir and soymilk kefir also significantly decreased the serum OVA‐specific IgE and IgG1 levels for both groups, but not those of the IgG2a analogues. Consumption of milk kefir and soymilk kefir suppressed the IgE and IgG1 responses and altered the intestinal microflora in our supplemented group, suggesting that milk kefir and soymilk kefir may be considered among the more promising food components in terms of preventing food allergy and enhancement of mucosal resistance to gastrointestinal pathogen infection. Copyright © 2006 Society of Chemical Industry 相似文献
993.
Theoretical results relevant to the design of a vertical Δκ switch are presented. The principle of a Δκ switch is the modulation of the coupling length by the application of an even electrooptic perturbation on the coupling region. Power switching requires that ΔκL =π/2. The initial state can be tuned electrically. The coupling length and the change with the index perturbation depend on many factors, such as the thickness and the refractive index of the coupling layer. Based on an analytic solution of the eigenmodes and eigenindices of the symmetric structure, the author clarifies many of these dependencies and obtains the relationship between the switching length required for power crossover and the available index change. The merits of the Δκ switch are discussed, and its efficiency is compared with that of the conventional Δβ switch 相似文献
994.
995.
Chin A. Chen W.J. Chang T. Kao R.H. Lin B.C. Tsai C. Huang J.C.-M. 《Electron Device Letters, IEEE》1997,18(9):417-419
We have studied the inversion layer mobility of n-MOSFET's with thin-gate oxide of 20 to 70 Å. Direct relationship of electron mobility to oxide/channel interface roughness was obtained from measured mobility of MOSFET's and high-resolution TEM. By using a low-pressure oxidation process with native oxide removed in situ prior to oxidation, atomically smooth interface of oxide/channel was observed by high-resolution TEM for oxide thicknesses of 11 and 38 Å. The roughness increased to one to two monolayers of Si in a 55-Å oxide. Significant mobility improvement was obtained from these oxides with smoother interface than that from conventional furnace oxidation. Mobility reduction with decreasing oxide thickness was observed in the 20- and 35-Å oxide, with the same atomically smooth oxide/channel interface. This may be due to the remote Coulomb scattering from gate electrode or the gate field variation from poly-gate/oxide interface roughness 相似文献
996.
997.
瓦纽可夫熔炼炉直接炼铅新工艺探讨 总被引:1,自引:0,他引:1
介绍了瓦纽可夫炼铅炉的结构、冶金过程及其操作状况,评述了瓦纽可夫熔炼炉直接炼铅新工艺的特点。认为瓦纽可夫炼铅法不仅符合节能、环保要求,而且具有流程短、设备简单、效率高、投资省等优点。 相似文献
998.
I Gardner JS Leeder T Chin N Zahid JP Uetrecht 《Canadian Metallurgical Quarterly》1998,53(6):999-1008
Covalent binding of a reactive metabolite of clozapine to neutrophils or their precursors is thought to play a role in the development of clozapine-induced agranulocytosis. Immunoblotting studies with an anti-clozapine antiserum detected covalent binding of clozapine to human neutrophils in vitro when HOCl was used to generate clozapine reactive metabolite (major clozapine adducts of 31, 49, 58, 78, 86, 126, 160, and 204 kDa). In addition, incubating neutrophils with clozapine and H2O2 (major clozapine adducts of 49 and 58 kDa) or clozapine, H2O2, and human myeloperoxidase (major clozapine adducts of 31, 49, 58, and 126 kDa) also resulted in covalent binding of clozapine to the neutrophils. The covalent binding of clozapine to neutrophils was inhibited by extracellular glutathione when HOCl, but not H2O2 was used to generate reactive metabolite. We found that the antiserum against clozapine also recognized olanzapine, an antipsychotic drug that forms a similar reactive metabolite to clozapine but has not been associated with induction of agranulocytosis. Repeating the in vitro experiments with olanzapine revealed that the major olanzapine-modified polypeptides had molecular masses of 96, 130-170, and 218 kDa. Only relatively low levels of 31, 49, and 58 kDa adducts were observed. Clozapine-modified polypeptides also were detected in neutrophils from patients being treated with clozapine. A major 58-kDa clozapine-modified polypeptide was detected in all patients tested. In contrast, no drug-modified polypeptides were detected in neutrophils from patients taking olanzapine. The differences in covalent binding exhibited by the two compounds and, in particular, the lack of olanzapine binding to human neutrophils in vivo may help to explain the difference in toxicity of these two drugs. 相似文献
999.
ΓΔα/F and Δα/α0 (where Δα is the absorption change, α0 is the residual absorption, F is the applied electric field, and Γ is the optical confinement factor in the waveguide) have been separately proposed as the relevant figure of merit for electroabsorption waveguide modulators. Using a quantitative and systematic argument, the authors show that they are both necessary and important to the total performance of the modulator 相似文献
1000.
A hybrid neural network based method for halftoning and inverse halftoning of digital images is presented. The halftone image is performed by single-layer perceptron neural network (SLPNN), and its corresponding continuous-tone image is reconstructed by radial-basis function neural network (RBFNN). The combined training procedure produces halftone images and the corresponding continuous tone images at the same time. The PSNR performance and visual image quality of these contone images achieved is comparable to the well-known inverse halftoning methods. The resultant halftone images compared with the error diffusion halftone are visually good, too. Furthermore, we apply different kinds of halftone images to a bi-level image compression method, called Block Arithmetic Coding for Image Compression (BACIC), which is better than the current facsimile methods. 相似文献