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41.
The HTLV-I seroprevalence rate among the patients with Sj?gren's syndrome (SjS, 23.0%) was significantly higher than that among blood donors (3.4%). The age-adjusted summary odds ratio of HTLV-I infection among SjS patients as compared with blood donors was 3.1. The etiologic fraction, i.e., the proportion of SjS in the study population that are attributable to HTLV-I infection, was estimated to be 17.6%. Titers of serum antibodies to HTLV-I in the seropositive SjS patients were significantly higher than those among healthy carriers. IgM class antibodies were commonly detected in sera of SjS patients. Salivary IgA class antibodies were common among seropositive SjS patients, but not in HAM patients or in healthy subjects. The findings strongly suggest that HTLV-I is involved in the pathogenesis of the disease in a subset of patients with SjS in endemic areas.  相似文献   
42.
This paper presents a new method for power system planning which considers uncertainties of various system parameters as a part of the criterion function. The criterion function involves both the expected values of total system costs and the cost variances of different power plants. Previously, the authors proposed that these cost variances be evaluated from the existing power system plans in the form of the solutions to the inverse optimization problem, and then applied this procedure to the planning of power systems in Japan. However, because of the correlation between fuel and facility costs, the cost variances could not be determined as specific values. Here, to overcome this difficulty, the authors now introduce hydropower plants into the model as the so-called nonrisky elements and focus on the expenditure shares rather than the plant capacity shares. As a result, more reasonable results are obtained. This improved methodology is applied and the derived cost variances are shown. Further, using the resultant cost variances, the authors make Pareto-optimal power generation plans and demonstrate also the robustness of the method to price fluctuations.  相似文献   
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The two-channel system previously reported has been implemented in hardware using system parameters appropriate to consumer television. The basic system divides the spectrum into lowand high-frequency spatial components. The lows are coarsely sampled and finely quantized and the highs finely sampled and coarsely quantized using a companded, randomized quantizer. The purpose of this experiment was to demonstrate the potential of the system for low-cost practical application, to study the effect of the character of the randomizing noise, and to ascertain that there were no deleterious effects due to interlace, motion, or input noise. Theoretical noise calculations were qualitatively confirmed.  相似文献   
46.
Higher order effects such as third-order dispersion, shock effect, and soliton self-frequency shift on all-optical logic gates that use asymmetric nonlinear optical fiber couplers are investigated with the beam propagation method, and it is found that third-order dispersion seriously affects the operations of logic devices. In contrast to the case of nonvanishing third-order dispersion, the radiation is stimulated, and consequently the operations of the logic devices are degraded. In order to diminish the degradation, the bandwidth limited amplification is introduced. The logic functions can be improved by trapping only the soliton components in the finite gain-bandwidth  相似文献   
47.
A scalar finite-element method is used for investigating propagation characteristics of dual-mode highly elliptical-core fibers. The dispersion property, polarization modal birefringence, and spatial modal birefringence are calculated. To improve the accuracy of solutions, isoparametric curvilinear elements are introduced. The applicability of the scalar finite-element method for highly elliptical-core fibers is assessed by comparing the results obtained with the vector finite-element method. An approximate simple approach, in which an elliptical-core is replaced by an appropriate rectangular-core, is also examined  相似文献   
48.
1. Studies on insect protein protease inhibitors are summarized. Biochemical, genetic and physiological investigations of the silkworm are performed. 2. In addition, the properties and characteristics of fungal protease inhibitors from the silkworm (Bombyx mori) are described and their importance as defensive functions is emphasized. 3. This review also concerns comparative and evolutionary studies of protease inhibitors from various sources. 4. The biological significance of inhibitors is discussed in view of the extensive experimental results.  相似文献   
49.
Advanced IC packaging for the future applications   总被引:2,自引:0,他引:2  
The performance of electronic equipment is improving rapidly. Portable electronic equipment requires smaller and thinner packaging systems for saving space and miniaturization. In addition, highly integrated, high-speed applications demand improved electrical performance to minimize noise effects. As a result of these considerations, the role of IC packaging has expanded from its traditional role of protecting the integrity and performance of an IC, to being a central factor in the development of electronic system concepts. In developing the optimum system, packaging technology must be a prime design consideration to ensure optimum performance, reliability, and cost. Soldering technology and Printed Wiring Board (PWB) routing density are two of the major technological issues facing miniaturized packaging systems today. Chip Scale Package (CSP), which is a new concept in packaging technology has been introduced. This is an ideal technology to enable the design and manufacture of the next generation of electronic equipment, while overcoming many of the technological issues facing system development  相似文献   
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