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991.
We demonstrate that whether a good of a rival firm is a strategic substitute or a strategic complement is endogenously determined when the market inverse demand is hyperbolic. The relative competitiveness, which is expressed by the ratio of firms’ marginal costs, is the key factor. We derive optimal trade policies, which are dependent upon the firms’ form of strategic action. In particular, it is shown that if the home firm is relatively more efficient (inefficient) than the foreign rival, then it regards the rival’s choice variable as a strategic complement (substitute) and thus the optimal policy recommendation for the home government is to impose an export tax (to give an export subsidy) to the home firm. 相似文献
992.
Shiho Ishihara Takuya Matsumoto Takamasa Onoki Taiji Sohmura Atsushi Nakahira 《Materials science & engineering. C, Materials for biological applications》2009,29(6):1885-1888
Octacalcium phosphate (OCP) and adipic acid-intercalated complexed OCP (Adi-OCP) were synthesized. Moreover, we made ceramic bodies out of them through a hydrothermal hot-pressing (HHP) method. Characteristic features of both the powder and ceramics were investigated by the X-ray diffraction method (XRD). Surface morphology of the ceramics was observed by scanning electron microscopy (SEM). Density, compressive strength and pore size distribution of the ceramics were measured. Crystalline structure of the newly developed OCP ceramics had no phase transformation from the starting materials. Moreover, the newly developed OCP ceramics had good mechanical properties only through the HHP treatment with a temperature as low as 110 °C. In order to evaluate bioactivity, the ceramics were immersed in simulating body fluid (SBF). It was predicted that OCP and Adi-OCP had better bioactivity than that of conventional HAp ceramics. 相似文献
993.
K Matsumoto 《Canadian Metallurgical Quarterly》1995,57(2):109-122
Since 1973, the occurrence of respiratory tract infections due to P. aeruginosa has increased associated with the development of broad-spectrum penicillins. A clinical entity, diffuse panbronchiolitis (DPB) is a representative disease of chronic P. aeruginosa infections in Japan. In this paper, recent advances of research on pathogenesis and treatments of chronic P. aeruginosa lower respiratory tract infections in our department are reported. We examined sputum from patients with chronic P. aeruginosa infections under the electron microscope. Mucoid type of microcolonies were observed with fibrous matrix of exopolysaccharide. Neutrophils were found to be partially surrounding the microcolony in an attempt to defense. Debris was formed mainly by the destruction of the neutrophils. Most neutrophils were found full of phagocytized debris. These data support that instead of phagocytizing bacteria, neutrophils phagocytized debris and bacteria were not completely eradicated. This might be a factor in the pathogenesis of persistent colonization of P. aeruginosa. In the airways of patients with chronic airway diseases (CAD), neutrophils enhance the recruitment of more neutrophils through the production of neutrophil chemotactic factors such as interleukin-8 (IL-8) and LTB4, perpetuating a cycle of inflammation in the lung. We demonstrated increased levels of IL-8, a chemotactic cytokine, in bronchoalveolar lavage (BAL) fluid from patients with CAD associated with P. aeruginosa infections. We also documented a significant correlation between neutrophil numbers and IL-8 levels or IL-1 beta levels or neutrophil elastase levels in BAL fluids from patients with CAD. By immunohistochemical studies and in vitro data, three major sources of IL-8 in the airways of CAD patients were found to be alveolar macrophages, bronchial epithelial cells, and migrated neutrophils. In Japan, the clinical effectiveness of oral erythromycin (EM) for CAD, including DPB seems to be established, but its pharmacological mechanism remains unclear. In addition, we found a marked decrease of IL-8 levels in BAL fluid from two patients with CAD after treatment with EM. Therefore, we postulated that EM inhibited IL-8 production by stimulated respiratory cells. EM and Roxythromycin, suppressed IL-8 production in Pseudomonas-stimulated neutrophils in a dose-dependent manner. 1 alpha, 25-dihydroxy vitamin D3 also inhibited neutrophil-derived IL-8. Our data encourage the development of new anti-IL-8 agents against persistent P. aeruginosa lower respiratory tract infections. 相似文献
994.
Ishiwata S. Yamakage T. Tsuboi Y. Shimazawa T. Kitazawa T. Michinaka S. Yahagi K. Takeda H. Oue A. Kodama T. Matsumoto N. Kamei T. Saito M. Miyamori T. Ootomo G. Matsui M. 《Solid-State Circuits, IEEE Journal of》2003,38(3):530-540
A single-chip MPEG-2 MP@ML codec, integrating 3.8M gates on a 72-mm/sup 2/ die, is described. The codec employs a heterogeneous multiprocessor architecture in which six microprocessors with the same instruction set but different customization execute specific tasks such as video and audio concurrently. The microprocessor, developed for digital media processing, provides various extensions such as a very-long-instruction-word coprocessor, digital signal processor instructions, and hardware engines. Making full use of the extensions and optimizing the architecture of each microprocessor based upon the nature of specific tasks, the chip can execute not only MPEG-2 MP@ML video/audio/system encoding and decoding concurrently, but also MPEG-2 MP@HL decoding in real time. 相似文献
995.
996.
Matsumoto A. Sakiyama S. Tokunaga Y. Morie T. Dosho S. 《Solid-State Circuits, IEEE Journal of》2008,43(4):831-843
A practical method for coupled oscillator design is elaborated. The topology analysis of a coupled oscillator, the ways of simulating its sensitivity, initializing its operation, and the oscillation frequency enhancement with nMOS phase couplers are presented. We have developed a write strategy system for DVD with a coupled oscillator using these techniques. In addition, we have also developed a low-power-oriented multiphase generator for mobile phones with our newly devised multiphase level shift system (M-LS). The M-LS has established superiority in its low power consumption because of no short current. Moreover, we have applied the method of output phase-accuracy improvement using a resistor ring to the M-LS. Two test chips are fabricated and the design method is validated. The first coupled oscillator has a resolution of 32 ps and a phase accuracy of -1.0 to 0.8 LSB at 490 MHz, corresponding to 16times DVD write speed. The second one consumes 1 mA and has a high phase accuracy of 0.5 LSB at 123 MHz. 相似文献
997.
Noritaka Yusa Eiji Machida Ladislav Janousek Mihai Rebican Zhenmao Chen Kenzo Miya 《Nuclear Engineering and Design》2005,235(14):1157-1480
This paper evaluates the applicability of eddy current inversion techniques to the sizing of defects in Inconel welds with rough surfaces. For this purpose, a plate Inconel weld specimen, which models the welding of a stub tube in a boiling water nuclear reactor is fabricated, and artificial notches machined into the specimen. Eddy current inspections using six different eddy current probes are conducted and efficiencies were evaluated for the six probes for weld inspection. It is revealed that if suitable probes are applied, an Inconel weld does not cause large noise levels during eddy current inspections even though the surface of the weld is rough. Finally, reconstruction of the notches is performed using eddy current signals measured using the uniform eddy current probe that showed the best results among the six probes in this study. A simplified configuration is proposed in order to consider the complicated configuration of the welded specimen in numerical simulations. While reconstructed profiles of the notches are slightly larger than the true profiles, quite good agreements are obtained in spite of the simple approximation of the configuration, which reveals that eddy current testing would be an efficient non-destructive testing method for the sizing of defects in Inconel welds. 相似文献
998.
In this paper, we focus on the microscopic structure of the liquid-vapor interface and the effect of impurities such as surfactants or electrolytes in the aqueous solution on interfacial properties. We perform molecular dynamics (MD) simulations of a simple planar interface system and a bubble system in which a nanometer-size void region is maintained. In these MD systems, some static and dynamic properties of molecules near the interface are investigated and we elucidate some microscopic features of the interface. Especially, we show the difference of the dynamics of water molecules between the surfactant and electrolyte solutions. We also consider the definition of the interface at the molecular level which can treat the local and instantaneous structure, and discuss the physical properties which we calculate including the effect of molecular fluctuations of the interface. 相似文献
999.
1000.
J Murashima Y Ueki Y Matsunaga M Yano K Matsumoto S Miyake Y Tominaga K Eguchi K Yano 《Canadian Metallurgical Quarterly》1998,9(8):725-732
Low-density lipoprotein (LDL) adsorption using a dextran sulfate cellulose column is brought about by electrostatic binding between the positive charges of apolipoprotein B in LDL and the negative charges of dextran sulfate cellulose. There is general agreement that the initial contact phase in the coagulation pathway may be activated by a negatively charged surface such as dextran sulfate cellulose, resulting in the generation of bradykinin. We investigated whether the increase in the generation of bradykinin during LDL adsorption is accompanied by the activation of endogenous production of nitric oxide (NO) in patients with peripheral atherosclerosis. LDL adsorption therapy was repeated ten times over a period of 3 months in ten peripheral atherosclerosis patients. Treatment significantly reduced serum total cholesterol and LDL cholesterol levels. This was associated with a significant improvement in Fontaine's classification and ankle pressure index. We also measured the kinin-kallikrein system and plasma levels of NO in the same patients. The results showed that coagulation factors of the intrinsic pathway including high-molecular-weight kininogen and prekallikrein decreased markedly after initial adsorption compared with the levels before treatment. There was a marked increase in bradykinin and NO concentrations after the initial adsorption, compared with their levels before adsorption. Our results suggest that the generation of bradykinin and increased plasma levels of NO may contribute to the improvement in peripheral circulation after LDL adsorption in peripheral atherosclerosis patients. 相似文献