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81.
Denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene analysis were carried out to analyze the bacterial community in Zaopei during production of Chinese Luzhou‐flavor liquor. Primers PRBA338F and PRUN518R were used for DGGE. Polymerase chain reaction (PCR) for clone analysis was preformed with primers EU27F and 1490R. The results by DGGE showed that with increasing fermentation time the diversity of bacteria in Zaopei decreased and after one week, only one bacterium phylotype was dominant. Gene clone libraries (16S rRNA) containing 55 clonal sequences were constructed. The bacterial diversity shift observed by DGGE was also shown by the clone library analysis. Bacteria closely related to Lactobacillus acetotolerans appeared to play a key role during Chinese liquor fermentation.  相似文献   
82.
In this paper an overview is presented on R&D of medical imaging and image processing techniques in Japan during the last decade, focusing on case studies in the diagnosis of cardiac diseases.Various problems of image processing of left ventricular images obtained from x-ray, ultrasound and radionuclides are discussed. Also reviewed are boundary detection methods of left ventricular inner cavity and myocardium, analysis of left ventricular wall motion and various kinds of cardiac functions using conventional and newly developed methods, and display methods of these cardiac functions.Microcomputerized on-line image processing systems and a compound sector scan echocardiography using two probes developed for echocardiographic examinations are shown with some results in clinical applications.3-dimensional reconstruction methods of the left ventricle and other organs from multiple 2-dimensional images are shown with 3-dimensional shapes reconstructed from images by x-ray, ultrasound and radionuclides. Moreover, 3-dimensional functional images of the left ventricle are shown as well. Transferring the 3-dimensional consecutive left ventricular images during a cardiac cycle onto a CRT display under the control of a microprocessor, we can observe the pulsating 3-dimensional left ventricle on the CRT.  相似文献   
83.
The knock-out release of fission products is studied theoretically. The general equations of knock-out release are derived, assuming that a fission fragment passing through the surface of nuclear fuels knocks out a local region of the surface with an effective thickness and an effective cross-sectional area. Using these equations, the knock-out release of fission gases is calculated for various cases. The conditions under which the knock-out coefficients (the average number of uranium atoms knocked out by one fission fragment) is obtainable are clarified by experiments on the knock-out release of fission gases. A method of determining the effective thickness and the effective cross-sectional area of a knock-out region is proposed.  相似文献   
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Summary Polymer of α-substituted benzyl methacrylate was found to be used as a new type of positive electron-beam resist, which forms methacrylic acid units in the polymer chain on the exposure to electron-beam and can be developed using alkaline solution as a developer. The sensitivity was dependent on the bulkiness of the ester group and the number of ?-hydrogen atoms in the ester group. The sensitivity and γ-value of atactic poly(α, α-dimethylbenzyl methacrylate) were improved by a factor of more than three over poly (methyl methacrylate).  相似文献   
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We summarize the reliability growth models for hardware and software systems described by a stochastic process, where the underlying stochastic process is assumed to be a nonhomogeneous Poisson process (NHPP). The background of reliability growth modelling based on an NHPP is surveyed. The Duane model, which was first postulated as a reliability growth model and is commonly used, is first explained. Secondly, the Weibull growth and modified Weibull growth models for hardware systems and the exponential type growth and gamma type growth models for error detection for software systems are discussed. The parameter estimates can be obtained by maximum likelihood estimation. Finally, the goodness-of-fit tests based on chi-square, Cramér-von Mises and Kolmogorov-Smirnov statistics are presented for the reliability growth models based on an NHPP.  相似文献   
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The purpose of this paper is to study the filtering problems from the viewpoint of the information theory. For a linear system it is proved that the necessary and sufficient condition for maximizing the mutual information between a state and the estimate is to minimize the entropy of the estimation error. Then we derive the Kalman-Bucy filter for both the discrete-time and the continuous-time systems by an application of the information theory. Furthermore, the approach is extended to the nonlinear dynamical systems with noisy observations and then the information structures of the optimal filter for a continuous-time nonlinear system are made clear, which has been presented as the interesting open problems by Bucy.  相似文献   
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