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191.
Y. Ono Y. Miyazaki S. Yabuuchi H. KageshimaM. Nagase A. FujiwaraE. Ohta 《Thin solid films》2011,519(24):8505-8508
Magnetic properties of manganese (Mn) nanosilicide embedded in thin silicon-on-insulator (SOI) layers are investigated. Mn nanosilicide formed by Mn+ ion implantation into a thin SOI layer followed by a thermal annealing at 600-900 °C shows soft ferromagnetism or superparamagnetism at 5 K. A monotonic decrease of the saturation magnetization is observed with increasing temperature for post implantation annealing and consequently with increasing mean particle size of nanosilicide. In addition, the magnetization is found to be enhanced when the Si surrounding the Mn nanosilicide is selectively removed. These results indicate that the magnetic moment indeed arises from the nanosilicide and is sensitive to the interface conditions. 相似文献
192.
Kiyonobu Kasama Yujing Jiang Akihiko Hiro-Oka Noriyuki Yasufuku Hidefumi Sato 《Soils and Foundations》2011,51(4):575-589
Torrential rainfall in mid-July 2009 triggered numerous geodisasters such as slope failure and debris flow in Chugoku and Northern Kyushu areas of Japan. A number of slope failures and debris flows occurred in Yamaguchi and Fukuoka prefectures resulting in extensive damage to human life and infrastructure. One of the most serious geodisasters included a slope failure followed by debris flow at Sasaguri-machi and Fukuchi-machi, Fukuoka prefecture, Japan. This paper summarizes the results of geotechnical investigations on the geodisaster sites in Fukuoka prefecture. The geotechnical investigation included determining a series of grain size distributions, consistency limits and conducting direct box shear tests for collapsed soils collected at six disaster sites. The generation mechanisms of slope failure followed by debris flow were also investigated by analyzing the precipitation, topography, geology, and strength properties of the collapsed soils. Moreover, slope deformation and stability analyses were coupled with an unsaturated-saturated seepage analysis to investigate the slope failure mechanism. The main findings from the study are summarized as: The physical properties, such as the grain size distribution, the plastic limit and liquid limit of collapsed soils, are summarized and compared with the results of other failure slopes in the literature. The collapsed soil was characterized as being a well grained soil (the uniformity coefficient >50) and highly weathered (the ignition loss >5%), however, with regard to the liquid limit and plastic index, there were no remarkable findings. The original shear strength for collapsed soils with natural water content is relatively large and slope failure doesn't occur because the cohesion in the shear strength is induced by a suction force between the soil particles under unsaturated condition. However, water seepage into the soil induces a drastic decrease in the shear strength, which is mainly caused by a decrease in cohesion (losing suction) resulting from soil saturation. In addition, the drained/undrained condition in the shear process is also sensitive to shear strength. For example, both water seepage and the shear process with constant volume cause an approximate 30% reduction in shear strength for Fukuchi-machi and Sasaguri-machi soil samples. Therefore, the reduction of cohesive strength due to water seepage and the low permeability of the slope are the parameters which trigger geodisaster. Based on the results of slope deformation and a stability analyses which took the change in water pressure and cohesive strength into account, the geodisaster at Fukuchi-machi was simulated, it is reasonable to assume that the shallow failure near the top of slope occurred due to torrential precipitation of about 100 mm per hour which triggered a debris flow. 相似文献
193.
Significance of the detection of staphylococcal enterotoxin A gene in low fat milk which caused a serious outbreak of food poisoning 总被引:1,自引:0,他引:1
Yamashita K Kanazawa Y Ueno M Ohta H Kitaguchi M Kawakami T Iwasaki K Tsujisawa E Morino Y Tabita K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(4):186-190
In June 2000, there was a large-scale outbreak of food poisoning after consumption of Snow Brand low fat milk. In the evening of a day the incident made public, some cartons of low fat milk were brought to our laboratory for examination. Next day, we detected only staphylococcal enterotoxin (SE) A gene among SE (A-E) genes by PCR in left-over milk samples or samples from the same lots that patients had consumed. We presumed that the outbreak was caused by the intake of SEA. We subsequently confirmed the presence of SEA in these samples. To investigate the existence of SE (A-E) genes in milk, we examined 100 samples of commercial low fat milk and milk by PCR, but none of the genes was detected. We estimated the detection limit of SEA gene in low fat milk by PCR. Four strains of SEA-producing Staphylococcus aureus cultures were serially diluted in low fat milk. The SEA gene was detected at levels of 5.5 x 10(2) to 1.6 x 10(4) cfu/mL of S. aureus. These amounts of S. aureus are higher than the values in raw milk reported previously. Therefore we consider that SE genes in low fat milk should usually be undetectable by our PCR. This study shows that quick detection of SE genes by PCR is very helpful to analyze outbreaks, especially if no significant bacterium can be cultured. 相似文献
194.
This case study was designed to examine the self-defined health needs of families in one urban Western Australian community. We conducted 157 family interviews to examine the relationship between family sociodemographic variables and patterns of use of health services, which included services used within the previous 12 months, and what the family needed and wanted from these services. Questions covered perceptions of health, family health concerns and the role of the family health guardian. Quantitative analysis included frequencies, cross-tabulations, chi-squared tests and multiple regression analysis. Open-ended responses were categorised and analysed for common themes. Approximately 80 per cent of participants had used one or more health services during the previous 12 months and, despite 35.9 per cent of families having at least one family member with a long-standing illness, disability or infirmity, most (82.1 per cent) considered the family healthy. The correlational analysis revealed several associations. Predictably, younger persons reported higher health ratings and older persons had more health concerns. Larger families reported better perceived levels of health. Higher utilisation rates were recorded for families with children, who tended to use the general practitioner for general care and medication, whereas one-parent families used hospital and specialist care more often, and 98.7 per cent reported satisfaction with services. What they needed and wanted from their health service providers was 'full disclosure' and 'not being talked down to', and for specialists especially to be approachable and impart information simply and honestly. 相似文献
195.
S Ohue K Kohno K Kusunoki K Sadamoto S Ohta T Ueda S Sakaki 《Canadian Metallurgical Quarterly》1998,40(8):536-540
Although magnetic resonance angiography (MRA) is accepted for showing chronic intracranial stenotic or occlusive lesions, the method has not been practically examined in patients with acute cerebral ischaemia. We carried out three-dimensional time-of-flight MRA in six patients with acute ischaemia treated by local thrombolysis, and compared the findings with those of digital subtraction angiography (DSA). In all patients, MRA before thrombolysis clearly demonstrated the occluded arteries, which corresponded precisely to those shown by DSA. In four patients with complete recanalisation of the occluded vessels after thrombolysis, the recanalisation could be demonstrated by postoperative MRA. In one patient with reocclusion of the recanalised artery, repeat MRA also demonstrated the reocclusion, confirmed by DSA. These results suggest that MRA may be helpful for noninvasive investigation before and after thrombolysis. 相似文献
196.
H Horino T Mimura K Kagechika M Ohta H Kubo M Kitagawa 《Canadian Metallurgical Quarterly》1998,46(4):602-609
A series of 3,4-dihydro-3-hydroxy-4-[(5-oxo-3,4-diazabicyclo[4.1.0]hept- 2-en-2-yl)oxy]-2H-1-benzopyrans and their analogues were synthesized and evaluated on potassium channel opening and hypotensive activities. Compound (-)-13B with a (4-methyl-5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yl)oxy group for the 4-position of the benzopyran ring was 3 times as potent as EMD 57283 (II), the lead compound, in hypotensive activity. The results would demonstrate that 5-oxo-3,4-diazabicyclo[4.1.0]hept-2-en-2-yloxy moieties are effective as the substituents at the 4-position of benzopyran-type potassium channel openers. 相似文献
197.
Lipopeptides carrying a farnesyl thioether or a palmitic acid thioester and a farnesyl thioether were prepared from S-farnesyl cysteine methyl ester by N-terminal extension of the peptide chain employing the base labile Fmoc blocking group of the palladium(0) sensitive Aloc urethane. By means of this technique a lipohexapeptide representing the completely functionalized, i.e. palmitoylated and farnesylated C-terminus of the human N-Ras protein, was prepared. If acid labile blocking functions like the Boc group were used, upon deprotection an undesired addition of the acid to the double bonds of the farnesyl residue occurred. Therefore, acid labile blocking groups should not be employed in the synthesis of farnesylated lipopeptides. The lipopeptide methyl esters which carry only a farnesyl group do not inhibit protein farnesyl transferase, whereas palmitoylated peptides are weak inhibitors of this enzyme. 相似文献
198.
A 49-year-old female presented with a 2-year history of occipitalgia, a 3-month history of dysesthesia, and dull sensation of the left upper extremity. T1-weighted magnetic resonance (MR) imaging revealed a low-intensity mass without gadolinium-diethylenetriaminepenta-acetic acid enhancement extending from the cisterna magna to the spinal canal. T2-weighted MR imaging revealed a high-intensity mass. Neuroradiological findings were inadequate to establish the mass as intra-axial or extra-axial. Operative findings discovered an intra-axial mass which was totally removed. Histological examination found the mass was an oligoastrocytoma. Cerebellar glioma developing exophytically is very rare. Adequate surgical removal is possible and likely to be curative if total. 相似文献
199.
Tokuda T. Sakano Y. Mori D. Ohta J. Nunoshita M. Vaccaro P.O. Vorob'ev A. Kubota K. Saito N. 《Electronics letters》2004,40(21):1333-1334
A micromirror structure with SiGe/Si heteroepitaxial layer on a silicon-on-insulator (SOI) substrate using a 'Micro-origami' technique has been successfully fabricated. The micromirror is supported by two curved hinge structures. The device is driven by application of a current, and net angular displacements larger than 10/spl deg/ (static) and 30/spl deg/ (in resonance) were obtained. These values are comparable with or even larger than the reported values for other MEMS optical switches or beam scanning devices. The experimental results suggest that the movement is evoked by a thermal effect. The Micro-origami device has advantages of low operation voltage smaller than 2 V, and structural compatibility with the Si or SiGe LSIs. 相似文献
200.