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71.
We applied a Mo/B4C multilayer coating to a laminar holographic grating with 2400 grooves/mm and a 1-m radius of curvature. By use of synchrotron soft x rays the multilayer-coated grating was evaluated to have diffraction efficiencies of 3.1% and 0.017% for s- and p-polarized radiation, respectively, at a 6.7-nm wavelength at a 45.35 degrees grazing angle of incidence in the +1 (inside) grating order. Thus the polarizance was estimated to be 98.9% at least. The zero-order peak was suppressed by the destructive interference caused by the groove profile.  相似文献   
72.
We have successfully fabricated 1.3-/spl mu/m AlGaInAs strain-compensated multiple-quantum-well (MQW) buried-heterostructure (BH) lasers by narrow-stripe selective metalorganic vapor-phase epitaxy. Based on the optimization of AlGaInAs strain compensated MQW and the Al-oxidation-free BH process, we obtained a low-threshold current of 12.5 mA and a relaxation frequency of more than 10 GHz at 85/spl deg/C for Fabry-Perot lasers. For distributed feedback lasers, we demonstrated a 10-Gb/s operation and transmission of over 16 Km for a single mode fiber at 100/spl deg/C. Furthermore, a record-low 25.8-mA/sub p-p/ modulation current for a 10-Gb/s modulation at 100/spl deg/C was demonstrated with shorter cavity and high grating-coupling coefficient. A median life of more than 1/spl times/10/sup 5/ h at 85/spl deg/C was estimated after an aging test of over 5000 h for these lasers. These superior characteristics at high temperatures were achieved by the combination of the high differential gain of AlGaInAs strain compensated MQW and the BH structure.  相似文献   
73.
The manufacturing industries are now experiencing fierce pressure of competition from every corner on this planet. In addition, the advancement in computer networks and information technologies has been gradually reshaping the manufacturing companies by shifting from the industrial age to the information era. Due to these elevated competitiveness and advanced computer technology, a number of new manufacturing and management strategies (e.g., CE or CIM) have emerged for the innovation of manufacturing enterprises. Although they have different definitions and scopes, there are several common issues: inter-enterprise functions integration; inter-enterprise resources integration; and collaboration. This paper proposes a new multi-agent system (MAS) architecture to support the inter-enterprise functions/resources integration and collaboration over the networked environment, including the hybrid agent architecture and hybrid network architecture. In contrast to the existing agent architectures, the proposed agent architecture enables agents to exhibit the hybrid (continuous and discrete) behavior and interactions. In addition, our network architecture is more suitable for building the large-scale distributed manufacturing systems that are prone to dynamic random changes of their environment. Based on the proposed MAS architecture, a collaborative product development environment is implemented as a starting point, and a multidisciplinary team-oriented design problem is illustrated to provide the vision of the proposed MAS architecture.  相似文献   
74.
A model is proposed that describes the essential optical process in the recently observed resonant light scattering from a microsphere resonator that is strongly coupled to the substrate. The experimentally observed field patterns across the resonance can be reproduced quite well by a numerical calculation taking into account only a few vector spherical waves that are converted from nonpropagating to propagating waves at the substrate surface. Explicit consideration of the multiple-reflection effect is not necessary to reproduce the experimental results. Comparison of the experiment and the calculation suggests the splitting of degenerate resonance modes that have different azimuthal mode numbers within a single broad resonance line. These results are discussed on the basis of the strongly coupled nature of the system.  相似文献   
75.
With a fixed gate width under the condition where the focus of an acoustic lens was set inside the sample, we varied signal taking-in time. Discrimination was made between differences in time required for an ultrasonic signal reflected from the sample to reach the acoustic lens. This process also enabled three types of images to be obtained separately: the surface reflection wave image, a combination of images based on the interference of the surface reflection wave with surface acoustic waves, and the surface acoustic wave image. Thus it was presumed that this process also would reveal the causes of image contrast and allow an easy interpretation of images. Furthermore, the image resolution was improved, because the surface acoustic wave image was drawn by an ultrasonic beam produced by full-circular surface acoustic wave excitation propagating toward the center converging concentrically; the theoretical resolution was 0.4 times the value of the surface acoustic wave wavelength lambda(R) and independent of the defocus value of the acoustic lens. Several kinds of samples were observed with this method. The results showed that the new method permitted observation of the internal structures of samples while offering new knowledge through the data reflecting the ultrasonic wave damping and scatter drawn on the display.  相似文献   
76.
The bitter taste of oxyphenonium bromide, an antiacetylcholine drug, is suppressed by cyclodextrins. The extent of the suppression can be predicted from the electromotive force measurements with an oxyphenonium bromide-selective electrode. The relationship between the bitter taste intensity and the electromotive force holds true, regardless of the kind and concentration of natural and modified cyclodextrins. This result is explicable on the basis of the observation that both the bitter taste and the electric potential are determined by the concentration of free oxyphenonium bromide. Some implications and limitations of the present approach are discussed.  相似文献   
77.
We report measurements on the effects of4He coverage and pressure on the fourth sound propagation in superfluid3He in confined geometries of four different pore sizes.  相似文献   
78.
The purification of drebrin, an actin-binding protein that is specifically expressed in embryonic rat brain, was described previously. During the purification of drebrin, we found that an actin-binding protein of 54 kDa was also expressed at high levels in embryonic brain, and this protein was identified by immunoblotting as fascin. To explore the roles of fascin in brain development, we purified fascin from brains of infant rats and characterized it. We found that the actin-binding activity of fascin was strongly inhibited by drebrin. Fascin caused formation of actin bundles, a process that was inhibited in the presence of drebrin, as confirmed by electron microscopy and a low-speed centrifugation assay. In PC12 cells, fascin was localized in the filopodia of growth cones, whereas drebrin was localized in the basal region of growth cones. Our results suggest that fascin might play an important role in the organization of actin in filopodia and that this organization might be regulated by drebrin.  相似文献   
79.
The aim of this study was to determine whether chemo-endocrine therapy after the resection of liver metastasis from colorectal cancer would prevent recurrence in the remnant liver and prolong survival. Eleven colorectal cancer patients underwent hepatic resection for liver metastasis. Subsequently, they were administered Proglumide gastrin antagonist 1,200 mg/day + 5'-DFUR 800 mg/day for 2 years. In seven of them, MMC 6-10 mg and ADM 20 mg were infused intra-arterially every two weeks alternately for one year. In four of them, 5-FU 250 mg/day was infused for seven days continuously intra-arterially every two weeks for one year. Recurrence in the remnant liver occurred in four of 11 patients. All of these patients underwent repeated hepatectomy. The mean disease-free survival in the remnant liver was 37 months and the five-year survival rate was 91%. These results indicate that intra-arterial chemotherapy with gastrin receptor antagonist might be effective for adjuvant therapy in patients with resectable liver metastasis from colorectal cancer.  相似文献   
80.
In contrast to conventional T cells, natural killer (NK) 1.1+ T cell receptor (TCR)-alpha/beta+ (NK1+T) cells, NK cells, and intestinal intraepithelial lymphocytes (IELs) bearing CD8-alpha/alpha chains constitutively express the interleukin (IL)-2 receptor (R)beta/15Rbeta chain. Recent studies have indicated that IL-2Rbeta/15Rbeta chain is required for the development of these lymphocyte subsets, outlining the importance of IL-15. In this study, we investigated the development of these lymphocyte subsets in interferon regulatory factor 1-deficient (IRF-1-/-) mice. Surprisingly, all of these lymphocyte subsets were severely reduced in IRF-1-/- mice. Within CD8-alpha/alpha+ intestinal IEL subset, TCR-gamma/delta+ cells and TCR-alpha/beta+ cells were equally affected by IRF gene disruption. In contrast to intestinal TCR-gamma/delta+ cells, thymic TCR-gamma/delta+ cells developed normally in IRF-1-/- mice. Northern blot analysis further revealed that the induction of IL-15 messenger RNA was impaired in IRF-1-/- bone marrow cells, and the recovery of these lymphocyte subsets was observed when IRF-1-/- cells were cultured with IL-15 in vitro. These data indicate that IRF-1 regulates IL-15 gene expression, which may control the development of NK1+T cells, NK cells, and CD8-alpha/alpha+ IELs.  相似文献   
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