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61.
Five sterylglycosides (acylmono-, mono-, di tri- and tetraglycosylsterol) and a saponin were isolated from Adzuki beans and characterized. In the glycosylsterols, the principal component sterols were sitosterol and stigmasterol; the major sugar component was glucose. The glucose units were shown to be linked by β1,6-bonds. The three oligoglycosylsterols were shown to be gentiobiosylsterol, gentiotriosylsterol and gentiotetraosylsterol; the latter two are novel sterylglycosides. The saponin was identified as glucopyranosyl-(β1→2)-glucopyranurosyl-(β1→3′)-soyasapogenol B (Azukisaponin I) which had previously been found in Adzuki beans.  相似文献   
62.
The possibility of single-mode oscillation over a large cavity area for photonic crystal lasers emitting at the photonic band edge has resulted in much interest in such materials for new forms of solid-state laser. In this paper, we measure the photonic bandstructure in our sample and identify the lasing band edge. By mapping out the bandstructure at the /spl Gamma/-point, we have observed fine structure at the band edge. The experimental results are in good agreement with the theoretically predicted bandstructure. Above threshold, we observe a lasing peak at 965 nm at one of the band edges. The far-field distribution of the laser is measured, showing an annular profile and azimuthal polarization. Calculations on the far-field distribution at the lasing band edge suggest the annular profile is due to an anti-symmetric resonant mode.  相似文献   
63.
The optimization problem is studied for a queueing network consisting of one station and two parallel subordinate stations. After service completion at the first station, the job is divided into two subjobs and each of them enters one of the subordinate stations. The service rate at the first station is controlled in order to minimize the expected total discounted cost or the long-run average expected cost  相似文献   
64.
65.
The stages of mental rotation of complicated three-dimensional figures were studied using the intracortical interaction mapping. The role of the parietal areas in the mental rotation was shown. The frontal, central and the right temporal areas are involved in the prerotation setup. Both frontal areas and the left temporo-parieto-occipital areas participate in decision making and verbal response. In the case of unsuccessful task solving the process stops at the prerotation setup stage. During the verbal control the zones of the predominant connections at the first 3 stages are close to those in the background activity.  相似文献   
66.
67.
The Escherichia coli quinol oxidase, cytochrome bo, is closely related to the cytochrome c oxidase, cytochrome aa3 in all aspects of its structure and function except for the replacement of the cytochrome-c-binding site and its attendant CuA prosthetic group with a quinone-binding site. The putative oxidation of quinol by ferrihaem (cytochrome b) at this site in sequential one-electron steps requires the stabilisation of semiquinone. We have observed, by electron paramagnetic resonance, the properties of a ubisemiquinone radical in appropriately poised samples of purified enzyme reconstituted with excess ubiquinone. The ubisemiquinone is highly stabilised with respect to free ubisemiquinone; significant free radical can be observed even at pH 7.0, while at pH 9.0 the stability constant is 5-10. The pH dependence of the stability constant indicates that the anionic form of the semiquinone predominates above pH 7.5. The two-electron couple has an Em7 of approximately 70 mV. Below pH 9, the pH dependence of the two-electron couple is -60mV/pH, indicative of a 2H+/2e- reaction. The line width of the EPR spectrum is approximately 0.9 mT, which is consistent with a ubisemiquinone anion. In comparison with other respiratory chain Q.- species that have been described, the relaxation rate in the presence of reduced haems appears comparable to magnetically isolated Q.- radicals. Partially resolved splittings of approximately 0.4 mT can be observed in the spectrum of Q.-bo (QH.bo).  相似文献   
68.
As far as we know, IgA and IgG antibodies to purified house dust mite allergens Der fI and Der fII in nasal secretions have never been documented. Therefore, we determined specific IgA, SIgA and IgG antibodies (abs) to crude extract of D. farinae and its purified allergens Der fI and der f II in nasal secretions collected by aspiration from 34 normal subjects, 25 untreated nasal allergic patients and 28 treated nasal allergic patients on parenteral immunotherapy by means of an avidin-biotin ELISA. The following results were obtained. (1) The specific IgA, SIgA and IgG abs to each of the three kinds of allergens correlated with each other. The groups of patients with nasal allergy (both treated and untreated) showed higher levels of specific IgA, SIgA and IgG abs to the allergens than the normal group. (2) In the group of treated patients, the levels of specific abs were not correlated with the clinical improvement of symptoms or the degree of response to nasal challenge. (3) The treated patients failed to show significantly higher levels of abs in nasal secretions than the untreated patients. (4) The specific IgA and SIgA abs in nasal secretions seemed to be predominantly produced locally, and IgG abs might be transudated from the circulation.  相似文献   
69.
A human and a robot will carry out a task which is not attainable by themselves. In particular, a human recognizes environment and plans his trajectory without collision with obstacles. On the other hand, a robot generates a controlled force more than a human. In this paper, the best combination of human ability and robot capacity is considered. Based on force commands from a human, a robot supports it A reaction torque observer is implemented in a robot to observe an environmental disturbance. Environmental disturbance is classified into translational and rotational direction modes. As a result, adaptive force control in each mode is attained. Dual compliance control is applied to a wheelchair. A wheelchair that has the abilities of power-assist and relaxation of contact force is developed in this paper. As a result, operationality and stability are improved. The numerical and experimental results show the viability of the proposed method.  相似文献   
70.
A high-speed switching, as fast as 300 ps, of spontaneous emission is achieved in the recently developed quantum-confined field-effect light emitting triode. As a result of the combination of the field control of radiative life time with modulation of carrier-generation rate, the light intensity modulation does not rely on changes in carrier population at all but on the field control of the radiative life time in the quantum well structure of the device. Elaborated is the allowance for the deviation of the modulation depth of injection current from an optimum value in the modulation scheme  相似文献   
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