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101.
Neuropathy is a frequent complication in diabetes mellitus. Since the involvement of the autonomic nervous system indicates a poor prognosis, early detection and subsequent management are important. Analysis of heart rate variability (HRV) provides a quantitative measure of sympathovagal modulation activities on the heart and has been proven to be useful for the early assessment of the diabetic autonomic neuropathy. We recently developed a simple method of measuring pulse wave velocity (PWV) to evaluate sympathetic nervous activity in the vascular system. In this paper, we examined 33 diabetic patients with and without peripheral neuropathy (15 and 18 respectively) using these methods. In time domain analysis, the mean heart rate, standard deviation and coefficient of variation of HRVs significantly differed between these two groups, whereas the indices of PWVs did not show a significant difference. In frequency domain analysis of HRV, both low and high frequency components were decreased, and the low frequency component in normalized unit did not increase after standing in patients with peripheral neuropathy. We previously reported that the mean PWV decreased after standing in patients with diabetic neuropathy. This disagreement suggests that beta sympathetic dysfunction precedes alpha sympathetic dysfunction in diabetic neuropathy. 相似文献
102.
A p-type diamond metal semiconductor field-effect transistor (MESFET) structure, utilizing a boron pulse-doped layer as the conducting channel, has been successfully fabricated. The pulse-doped structure consists of an undoped diamond buffer layer, a highly doped thin diamond active layer, and an undoped diamond cap layer grown by the microwave plasma assisted chemical vapor deposition method. It is shown that this field-effect transistor with a gate length of 4 μm and the gate width of 39 μm exhibits an extrinsic transconductance of 116 μS/mm with both pinch-off characteristics and current saturation 相似文献
103.
Jun-ichi Kokado Natsuo Hatta Hirohiko Takuda Shiomi Kikuchi Tetsu Hirabayashi 《国际钢铁研究》1985,56(12):619-624
It has been ascertained whether or not the model capable of predicting the stress-strain relation of plain carbon steels, previously proposed, is applicable to the estimation of mill loads in the finishing process (consisting of six mill stands) of a hot strip mill. An appreciably good agreement with the predicted and measured mill load values has been obtained in the earlier passes where the strip microstructure is regarded to have completed static recrystallization, and the predicted mill loads in the later passes have been far less than the measured load owing to the effect of the strain accumulated in the previous rolling process. Then, a simple model to predict the accumulated strain has been constructed and introduced into the calculation of mill loads. As a result, the predicted mill loads have been fairly improved over the whole passes in the finishing process. 相似文献
104.
105.
The nitrogen gas adsorption isotherms at ?195°C on modified cellulose acetate ultrathin membranes were measured, and the surface area of the pores was determined by the method employed by Cranston and Inkley. A relationship between reverse osmosis characteristics and the mean pore radius was correlated, and it was observed that any method (such as longer evaporation period, heat treatment, or reduction of swelling agent) reducing the mean pore radius to below 20–22 Å improves membrane characteristics of reverse osmosis separation significantly. 相似文献
106.
Multiwatt internal-matching techniques for multichip power GaAs f.e.t.s at 11 GHz and 12 GHz bands have been developed, adopting a lumped-element input circuit and a semidistributed output circuit. The internally matched device for the 11 GHz band exhibits 4 W power output with 3.4 dB associated gain, and the 12 GHz device 3.6 W power output with 3 dB associated gain. 相似文献
107.
Global warming is one of the most serious issues in today's world. Various innovative technologies have been proposed for the reduction of CO2 emissions and the mitigation of global warming. They include (1) the WENET project, inaugurated in 1993 by the government of Japan, in which electricity produced by photovoltaic systems in vast areas such as the Sahara Desert, or by hydropower systems, is converted to hydrogen for transport to demand sites, and (2) Steinberg's Hydrocarb process, in which fossil fuels and biomass are coprocessed to produce carbon and methanol. While Japan is resource-poor, it is located relatively close to Southeast Asia and Australia, which are large regions with abundant solar energy. This paper describes an investigation of the prospects for the adoption of these innovative technologies by Japan and surrounding resource regions in the next 30 to 40 years. An optimizing energy model is developed for the purpose, and the simulation results provide several interesting suggestions regarding Japan's future strategy for combatting global warming. 相似文献
108.
A safety analysis for the design of International Thermonuclear Experimental Reactor (ITER) in the Conceptual Design Activity stage was performed by the GEMSAFE methodology, and its results were compared with those of Fusion Experimental Reactor (FER), a Japan's facility planned next to JT-60. The objectives of this study are to confirm the applicability of GEMSAFE to ITER and to select design basis events of ITER and identify R&D items with comparison to FER. Function-Based Safety Analyses (FBSA) were carred out to select 19 and 25 design basis events for FER and ITER, respectively. The major reason for the difference is that ITER has a class-2 RI source, e.g., tritium of 7.5 × 105 Ci in mobile form, in the coolant for the first wall and blankets as well as a class-3 RI source, e.g., the immobile tritium of 2.2×107 Ci absorbed in first wall and dust. 相似文献
109.
S Minagawa M Ishida K Shimakura Y Nagashima K Shiomi 《Canadian Metallurgical Quarterly》1997,118(2):381-386
We have isolated a novel retina-specific gene, retinal fascin, encoding a new member of actin-bundling protein gene family, from a bovine retina cDNA library. The cDNA encodes a 492 amino acid protein which shows 36-57% amino acid identity with three vertebrate fascins, echinoid fascin and Drosophila singed gene. Northern blot analysis revealed that retinal fascin mRNA was exclusively expressed in the eye and not seen in other tissues examined. In situ hybridization analysis indicated that retinal fascin mRNA signals were found only in the inner segment of the photoreceptor layer and outer nuclear layer, indicating that retinal fascin was specifically expressed in photoreceptor cells. As fascins are actin-bundling proteins important for constructing several intracellular structures, retinal fascin might play a pivotal role in photoreceptor cell-specific events, such as disk morphogenesis. 相似文献
110.