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101.
102.
Solving fuzzy shortest path problems by neural networks 总被引:1,自引:0,他引:1
In this paper, we introduce the neural networks for solving fuzzy shortest path problems. The penalization of the neural networks is realized after transforming into crisp shortest path model. The procedure and efficiency of this approach are shown with numerical simulations. 相似文献
103.
This paper describes realtime network management support systems which have been developed forntt’s telephone network. In particular, the advanced traffic observation and management information collecting system referred to as Atomics and the traffic congestion control system referred to astcs are presented. The purpose of the development, concept, functions and capabilities of each system are explained. Examples of powerful realtime network management supported by Atomics andTSC are also presented. 相似文献
104.
Cyclooxygenase (COX)-2 is induced by proinflammatory cytokines such as interleukin (IL)-1 beta, cytokines produced from helper T cell subpopulation Th 1, such as interferon-gamma and tumor necrosis factor-beta. Cytokines produced by the T cell such as IL-4, IL-10, and IL-13 down-regulate induction of COX-2. The novel MAP kinase pathway, JNK and/or p 38, are important intracellular signaling pathways for induction of COX-2. The increased production of prostaglandin E2 by upregulation of COX-2 increases IL-6 production. By utilizing a COX-2 blocker, it is possible to decrease IL-6 production via reduction of prostanoid production, thereby attenuating the systemic inflammatory response. Nitric oxide (NO) and prostanoids are also known to interact and regulate each other. It is important to note the interactions between prostanoids and cytokines or other inflammatory mediators such as NO in understanding the mechanism of the anti-inflammatory effects of prostanoid regulation. 相似文献
105.
Tea catechins, (-)-epigallocatechin-3-gallate (EGCg) and (-)-epigallocatechin (EGC), have been reported to suppress oxidation of plasma low density lipoprotein (LDL) in vitro. If dietary catechins can be efficiently incorporated into human blood plasma, anti-atherosclerotic effects in preventing oxidative modification of LDL would be expected. In this study, a newly developed chemiluminescence detection-high pressure liquid chromatography (CL-HPLC) method for measuring plasma catechins was used and the incorporation of EGCg and EGC into human plasma was investigated. Healthy subjects orally ingested 3, 5, or 7 capsules of green tea extract (corresponding to 225, 375, and 525 mg EGCg and 7.5, 12.5, and 17.5 mg EGC, respectively). The plasma EGCg and EGC concentrations before the administration were all below the detection limit (< 2 pmol/ml), but 90 min after, significantly and dose-dependently increased to 657, 4300, and 4410 pmol EGCg/ml, and 35, 144, and 255 pmol EGC/ml, in the subjects who received 3, 5, and 7 capsules, respectively. Both EGCg and EGC levels detected in plasma corresponded to 0.2-2.0% of the ingested amount. Catechin intake had no effect on the basal level of endogenous antioxidants (alpha-tocopherol, beta-carotene, and lycopene) or of lipids in plasma. These results suggested that drinking green tea daily would contribute to maintain plasma catechin levels sufficient to exert antioxidant activity against oxidative modification of lipoproteins in blood circulation systems. 相似文献
106.
O Ohara Y Gahara T Miyake H Teraoka T Kitamura 《Canadian Metallurgical Quarterly》1993,121(2):387-395
The existence of a neurofilament-deficient mutant of Japanese quail was recently documented (Yamasaki, H., C. Itakura, and M. Mizutani. 1991. Acta Neuropathol. 82:427-434), but the genetic events leading to the neurofilament deficiency have yet to be determined. Our molecular biological analyses revealed that the expression of neurofilament-L (NF-L) gene was specifically repressed in neurons of this mutant. To search for mutation(s) responsible for the shutdown of this gene expression, we cloned and sequenced the NF-L genes in the wild-type and mutant quails. It is eventually found that the NF-L gene in the mutant includes a nonsense mutation at the deduced amino acid residue 114, indicating that the mutant is incapable of producing even a trace amount of polymerization-competent NF-L protein at any situation. The identification of this nonsense mutation provides us with a solid basis on which molecular mechanisms underlying the alteration in the neuronal cytoskeletal architecture in the mutant should be interpreted. 相似文献
107.
Seiji Isoda Masaki Tsuji Masayoshi Ohara Akiyoshi Kawaguchi Ken-ichi Katayama 《Polymer》1983,24(9):1155-1161
The crystal structure of β-form poly(p-xylylene) is analysed starting from a high-resolution image of a single crystal of this polymer. The high-resolution image corresponding to the projection of molecules onto the ab-plane along the chain axis shows clearly the mutual position of each molecule in a unit cell. The molecules are aligned wavily in the direction along the a-axis and the rough positions of their centres in a unit cell can be determined from the image. The refinement of the structure is carried out by the usual least-squares method using the intensities of electron and X-ray diffractions. The space group of the β-form is trigonal, P3, and the lattice dimensions are a=2.052 nm, c=0.655 nm and γ=120°. The unit cell contains 16 molecules and one of them is considered to occupy statistically one of three equivalent orientations so as to satisfy the P3 symmetry. 相似文献
108.
Experiments using partial report techniques have typically failed to find left-right visual field differences in the recognition of tachistoscopically presented letter rows. Such data represent a difficulty for theories that emphasize the relevance of cerebral hemispheric asymmetry. It is contended that the end items of a display are critical, and that a truly symmetric display should have both a left and a right end item in each visual field. In the present experiments with 36 righthanded university students, partial report procedures were employed, but a gap was placed between the left and right halves of the display. In the 1st experiment, a single-letter spatial probe procedure was used, and a clear right visual field superiority was found. In the 2nd experiment, a hemifield report procedure was used; the presence of a gap in the display enhanced the right visual field superiority, especially for shorter strings of letters. Results indicate that right visual field superiority can be obtained with partial report procedures under appropriate conditions. (French summary) (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Photoelectrochemical investigations were undertaken on energy transfer and other interactions between chlorophyll-a (Chl-a) and β-carotene (Car) in lipid monolayers. A heterobilayer composed of a Chl-a-lecithin monolayer and a Car- lecithin monolayer was prepared on an SnO2 semiconductor electrode by Langmuir-Blodgett techniques. When the bilayer-coated electrode was irradiated in an aqueous electrolyte, anodic photocurrents due to the sensitizations by Chl-a and Car respectively were observed. The photocurrent efficiency (ratio of photons to electrons) was much for Car (about 10-3) than for Chl-a (about 10-1). This large difference permits a quantitative estimation of the energy transfer from Car to Chl-a, based on the concept that the energy transfer results in an increase in the Car- induced sensitized photocurrent. The effect of added Chl-a on the Car photocurrent was measured for heterobilayers with various Chl-a-to-Car molar ratios. The experimental results, as well as theoretical calculations, showed that the Car-to- Chl-a energy transfer is inefficient. The effect of Car on the Chl-a-sensitized photocurrent was also studied with the same bilayer system. The effect was shown to be complex depending on the Car content. A lowering of the Chl-a photocurrent occurred at high Car contents, which is considered to reflect the quenching of the Chl-a excited triplet by Car. The usefulness of the present photoelectrochemical approach for the study of energy transfer between the photosynthetic pigments is demonstrated. 相似文献
110.