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81.
Strain-controlled fatigue tests were conducted on carbon and low-alloy steels in high-temperature water containing controlled amounts of oxygen, in order to determine quantitatively the reduction of fatigue strength due to factors such as the strain rate and the environmental testing conditions such as temperature and dissolved oxygen content. For each of these factors, the effect on fatigue strength was separately quantified and parametric equations were derived with reference to the basic fatigue curve obtained in air at room temperature. Using the formulas thus obtained, generalized expressions for predicting the expected fatigue life of a given material under specified combinations of strain amplitude and environmental conditions were deduced. Based on these generalized expressions, “fatigue strength correction factors for environmental effectsrd are proposed, which can be conveniently used in combination with the design fatigue curve given in the ASME Boiler and Pressure Vessel Code, Section III to account for fatigue strength reduction under severe service conditions. 相似文献
82.
T Sankai H Iso H Imano T Ohira T Tanigawa T Shimamoto A Kitamura S Sato Y Naito M Kiyama T Okamura Y Nakagawa M Iida Y Komachi 《Canadian Metallurgical Quarterly》1998,45(6):552-563
PURPOSE: We conducted an epidemiological study of survival and disability in stroke in three Japanese communities to seek community strategies for improvement in survival and disability. METHODS: A total of 297 first-ever strokes were identified between 1988 and 1992 in three rural communities (total population = 47,000) located in Akita and Ibaraki. We analyzed survival rates and activity of daily living by sex, age-group and stroke subtypes. Successful review of computed tomography (CT) for 84 percent of the strokes (249 out of 297) was possible and the data were used for subtype analyses. RESULTS: For all strokes (n = 297) survival rates were 85% for 30 day, 70% for one year, 62% for three year. The rates tended to be lower in women than in men. The rates were lowest in ages less than 60 at thirty day, and in ages 80 and older at the end of the first and third year. Intracerebral hemorrhage with ventricular rupture, subarachnoid hemorrhage and cortical cerebral infarction had lower survival rates than intracerebral hemorrhage without ventricular rupture and lacunar infarction. Based on Cox's proportional hazard model, risk ratio for death was 2.07 in ages 70-79, and 3.80 in ages 80 and older compared with ages 60-69. The risk ratio was 3.46 for intracerebral hemorrhage with ventricular rupture, 3.38 for subarachnoid hemorrhage and 2.46 for cortical cerebral infarction compared with lacunar infarction. The proportion of stroke survivors who need assistance from others in the first and third years tended to be higher in women than in men. The proportion was higher in older patients than in the younger, and higher for intracerebral hemorrhage with ventricular rupture and cortical cerebral infarction than in other subtypes of stroke. From logistic regression analysis, the odds ratio for disability in the first year was 6.55 for ages 80 and older compared with ages 60-69. The odds ratio was 5.61 for intracerebral hemorrhage with ventricular rupture, 4.53 for cortical cerebral infarction compared with lacunar infarction. In the third year the odds ratio was significant for ages 70-79, and decreased for intracerebral hemorrhage with ventricular rupture (odds ratio = 2.98), and increased for cortical cerebral infarction (odds ratio = 6.06). CONCLUSIONS: Survival and disability in stroke depended on age and stroke subtypes. Even after age adjustment, stroke subtypes with large cerebral involvement had worse prognosis than stroke subtypes. Community-based hypertension control programs are important to prevent any subtypes of stroke. Stroke subtypes as well as age should be taken into account to develop effective care and medical treatments for strokes. 相似文献
83.
T Iida M Kanzaki A Nakama Y Kokubo T Maruyama C Kaneuchi 《Canadian Metallurgical Quarterly》1998,60(12):1341-1343
The Listeria monocytogenes-carrying rates were 100% for listeriosis patients and 1.3% for healthy humans. The L. monocytogenes contamination rates for retail sliced beef (34.2%) and pork (36.4%) were significantly higher (p < 0.05) than those for cattle (2.0%) and pigs (0.8%) and for cattle (4.9%) and swine (7.4%) carcasses. The percentages of serotypes 1/2a, 1/2b and 4b which are most dominant in human patients were high in isolates from fresh (90.0%) and processed (100%) fish and shellfish and imported natural cheese (96.7%). 相似文献
84.
Molecular characterization of the mutable flaked allele for flower variegation in the common morning glory 总被引:1,自引:0,他引:1
Force-velocity data at different temperatures (range, 10-35 degrees C) from intact fibre bundles are analysed to determine the temperature dependence of the maximal mechanical power output of fast and slow rat muscles. At 35 degrees C, the maximal mechanical power was approximately 250 kW m(-3) (=250 microW mm(-3)) in fast (probably an underestimate) and approximately 100 kW m(-3) in slow muscle. Within the more physiological temperature range (25-35 degrees C), the temperature coefficient (Q10) of maximum power was 2-2.5. In both muscles, the maximal power at 10 degrees C was only about 3-5% of that at 35 degrees C, the decrease being particularly pronounced at temperatures below 20 degrees C (Q10 of 5-7). 相似文献
85.
86.
K Iida K Fujita H Hirai H Goto S Miyazaki Y Arai H Iwaki M Otake S Sassa M Maemura T Nakayama H Kudo S Sakamoto 《Canadian Metallurgical Quarterly》1997,21(5):476-482
Polysaccharides extracted from human tubercle bacilli (specific substance of Maruyama [SSM]) have been clinically applied with satisfactory results. Thymidylate synthetase (TS) and thymidine kinase (TK) are key enzymes in de novo and salvage pathways for pyrimidine nucleotide synthesis. Well- and moderately well differentiated adenocarcinomas induced with 1,2-dimethylhydrazine (DMH) are widely distributed throughout the colorectal tract with high TK activity, and the poorly differentiated type is mainly restricted in the proximal colon and the cecum with high TS activity in rats. Subcutaneously injecting the rats with SSM reduced TS activity in colonic nontumorous regions, but in the tumorous regions it reduced TK activity compared with that of the DMH-treated rats without SSM treatment. SSM is suggested to reduce the colorectal carcinogenesis induced with DMH by inhibiting DNA synthesis in a de novo pathway, and to suppress the development of the tumors by decreasing DNA synthesis in the salvage pathway in rats. 相似文献
87.
Effects of epoxidized 1,2- or 1,4-polybutadienes on the zinc stearate/calcium stearate synergetic soap-induced thermal stabilization of poly(vinyl chloride) (PVC) were investigated by colorimetry. The remarkable stabilization effects of epoxidized polybutadienes could not be observed on the PVC films without synergetic soaps, while the stabilization of PVC was markedly enhanced by combined use of epoxidized polybutadienes with synergetic soaps. Excessive coloration of cool color-producing zinc chloride-polyene complexes that were the source of abrupt discoloration of stabilized PVC was retarded by using epoxidized polybutadienes together with synergetic soap. The synergism of epoxidized polybutadienes was enhanced with increasing epoxy contents. Moreover, the effect is also clearly dependent on degree of dispersion of epoxidized polybutadienes in PVC. Further colorimetries, infrared (IR), and X-ray photoelectron spectroscopies on the various PVC-containing epoxidized polybutadienes and zinc chloride indicated that the epoxy groups capture the zinc chloride. The synergistic effect between epoxidized polybutadienes and metal soap was ascribed to epoxidized polybutadienes serving as acceptors for the excessive cool color-producing zinc chloride produced by zinc stearate to retard the abrupt discoloration of stabilized PVC. The plate-out phenomenon appeared during the molding process of PVC-containing epoxy compounds was considerably retarded by epoxidized polybutadienes which modified polyols. The polyol-modifying epoxidized polybutadienes also exhibited a marked effect on PVC stabilization with metal soap. 相似文献
88.
Lumisight Table: an interactive view-dependent tabletop display 总被引:1,自引:0,他引:1
Kakehi Y. Iida M. Naemura T. Shirai Y. Matsushita M. Ohguro T. 《Computer Graphics and Applications, IEEE》2005,25(1):48-53
A novel tabletop display provides different images to different users surrounding the system. It can also capture users' gestures and physical objects on the tabletop. The Lumisight Table approach is based on the optical design of a special screen system composed of a building material called Lumisty and a Fresnel lens. The system combines these films and a lens with four projectors to display four different images, one for each user's view. In addition, we need appropriate input methods for this display media. In the current state of the project, we can control computers by placing physical objects on the display or placing our hands over the display. This screen system also makes it possible to use a camera to capture the appearance of the tabletop from inside of the system. Our other main idea is to develop attractive and specialized applications on the Lumisight Table, including games and applications for computer-supported cooperative-work (CSCW) environments. The projected images can be completely different from each other, or partially identical and partially different. Users can share the identical parts as public information, because all users can see it. This article is available with a short video documentary on CD-ROM. 相似文献
89.
H Iso T Shimamoto Y Naito S Sato A Kitamura M Iida M Konishi DR Jacobs Y Komachi 《Canadian Metallurgical Quarterly》1998,29(8):1510-1518
BACKGROUND AND PURPOSE: Although randomized clinical trials have demonstrated the benefit of antihypertensive treatment in preventing stroke, the effectiveness of community-based programs is largely unknown. We investigated long-term community-based prevention activities. METHODS: In rural northeastern Japan, people aged > or = 30 years numbered 3219 in the full intervention community and 1468 in the minimal intervention community in 1965. Systematic blood pressure screening and health education began in 1963. Stroke was registered through 1987. RESULTS: More than 80% of people aged 40 to 69 years were screened in both communities in the 1960s. One community charged for screening services after 1968, whereas the other community intensified intervention; subsequently, screening rates and the follow-up of hypertensive individuals declined in the minimal intervention community, especially in men. In men, stroke incidence declined more (P < 0.001) in the full intervention (42% in the period 1970 to 1975, 53% in the period 1976 to 1981, and 75% in the period 1982 to 1987) than in the minimal intervention community (5% increase, 20% decrease, and 29% decrease, respectively); in women, the stroke incidence declined about 45% to 65% in both communities. Changes in stroke prevalence paralleled those in stroke incidence. Trends in systolic blood pressure levels tend to explain the differential stroke rates in men. CONCLUSIONS: Delivery of hypertension control services through intensive, free, community-wide screening and health education was effective in prevention of stroke for men in a community. 相似文献
90.
M Iida 《Canadian Metallurgical Quarterly》1998,25(4):355-359
Ten subjects with diabetes mellitus and unilateral chronic foot ulcer were investigated. Local tissue concentrations of glucose and lactate were measured using the microdialysis method at a distance of 0.5-1 cm from the edge of the ulcer and in normal skin in the contralateral foot. Subcutaneous blood flow in the area investigated was measured using the 133Xewashout technique. The interstitial glucose concentration in the ulcer was found to be lower than in intact skin (8.0 +/- 1.0 mmol l-1 vs. 8.5 +/- 1.1 mmol l-1) (P < 0.02), and the interstitial lactate concentration was higher in the ulcer than in intact skin (3.2 +/- 0.2 mmol l-1 vs. 2.1 +/- 0.3 mmol l-1) (P < 0.01). The subcutaneous blood flow was on average 40% higher in the ulcer than in the intact skin. The calculated local glucose uptake and lactate outputs were twofold higher in the ulcer than in the intact skin. However, the molar ratio between lactate output and glucose uptake was approximately two, both in the ulcer and in the intact skin, indicating that the glucose metabolism was qualitatively the same in the two regions. 相似文献