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21.
E Kojima M Izumi T Tanabe M Matsuda T Shimizu A Murakami K Murakami 《Canadian Metallurgical Quarterly》1997,(37):171-172
The extent of genetic identity observed in the young individuals which were micropropagated from a single Eucalyptus individual was analyzed by using DNA-fingerprinting. Among 40,000 tissue-cultured-seedings of E.citriodora, 200 plants were randomly chosen so that each total DNA might be extracted from their leaves. Using these DNAs as template, PCR was performed with some primers we found in advance that leads polymorphism for DNA of E. citriodora. In this study, all over the 200 cases, the band pattern formed cDNA fragment on a gel after electrophoresis was the identical one mutually. 相似文献
22.
A torque sensorless control for a multi-degree-of-freedom manipulator is described. In the method, two disturbance observers are applied to each joint. One is used to realize a robust motion controller. The other is used to obtain a sensorless torque controller. A robust acceleration controller based on the disturbance observer is shown. To obtain the sensorless torque control, it is necessary to calculate the reaction torque when the mechanical system performs a force task. The calculation method for the reaction torque is explained. Then the method is expanded to workspace force control in the multi-degree-of-freedom manipulator. Several experimental results are shown to confirm the validity of the proposed sensorless force controller 相似文献
23.
T. Kawakami Y. Koide N. Teraguchi Y. Tomomura A. Suzuki Masanori Murakami 《Journal of Electronic Materials》1998,27(8):929-935
In order to prepare low resistance ohmic contacts to p-ZnSn by the “deposition and annealing (DA)” technique which has been
extensively used for GaAs and Si-based devices, formation of a heavily doped layer by the p-ZnSe/metal reaction is required.
For p-ZnSe/Ni contacts, Ni and Se reacted preferentially at the ZnSe/Ni interface upon annealing at temperatures higher than
250°C. However, capacitance-voltage measurements showed that the net acceptor concentration (NA-ND) close to the p-ZnSe/Ni interface was reduced upon the Ni/ZnSe reaction, resulting in high contact resistance. For p-ZnSe/Au
contacts, neither Au/ZnSe reaction nor reduction of the acceptor concentration were observed after annealing at temperatures
lower than 300°C. This indicates that although the metal/p-ZnSe reaction is mandatory to prepare a heavily doped layer, the
reaction induced an increase in the compensation donors in the p-ZnSe substrate. In order to increase the acceptor concentration
in the vicinity of the p-ZnSe/metal interface through diffusion from the contact materials, Li or O which was reported to
play the role of an acceptor in ZnSe was deposited with a contact metal and annealed at elevated temperatures. Ni or Ag was
selected as the contact metal, because these metals were expected to enhance Li or O doping by reacting with ZnSe. However,
the current density-voltage characteristics of the Li(N)/Ni and Ag(O) contacts exhibited rectifying behavior, and the contact
resistances increased with increasing annealing temperature. The present results indicated that, even though the acceptor
concentration in the p-ZnSe substrate increased by diffusion of the dopants from the contact elements, an increment of the
compensation donors was larger than that of the acceptors. The present experiments indicated that preparation of low resistance
ohmic contacts by forming a heavily doped intermediate layer between p-ZnSe and metal is extremely difficult by the DA technique. 相似文献
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T Kawai H Hiranuma M Kishino S Murakami M Sakuda H Fuchihata 《Canadian Metallurgical Quarterly》1998,86(3):376-381
BACKGROUND: Although the airway epithelium participates in inflammation and repair, the circadian expression of epithelial cell markers involved in these processes has not been investigated. OBJECTIVE: We sought to determine whether expression of CD51 (vitronectin and fibronectin receptor), CD54 (intercellular adhesion molecule-1), HLA-DR (activation marker), CD29 (beta1 integrin), CD49b (collagen receptor), and CD11b (complement receptor) exhibit a circadian rhythm in asthma. METHODS: Eleven patients with nocturnal asthma (NA), 9 subjects with nonnocturnal asthma (NNA), and 10 control subjects underwent bronchoscopy at 4 PM and 4 AM in a random order 1 week apart, with brushing of the proximal and distal airways. The percentage of cells staining for a particular marker was determined. RESULTS: At 4 PM, HLA-DR in the proximal airways and CD54 in the distal airways was significantly greater in control subjects as compared with asthmatic subjects (HLA-DR, control subjects: 10.0% [range, 5.0% to 21.0%]; NNA: 8.0% [range, 4.0% to 14.5%] NA: 3.5% [range, 2.0% to 6.0%], P = .01; CD54, control subjects: 17.0% [range, 8.0% to 25.0%], NNA: 8.0% [range, 5.3% to 11.5%], NA: 7.0% [range, 4.0% to 15.0%], P = .O;). At 4 AM, CD51 in the distal airways was significantly greater in patients with NA as compared with patients with NNA and control subjects (control subjects, 23.0% [range, 13.8% to 30.5%]; NNA, 32.0% [range, 13.0% to 35.0%]; NA, 40.0% [range, 23.0% to 50.0%], P = .05). Expression of CD51 in the distal airways correlated with the degree of airway obstruction (r = -0.57, P = .001). Control subjects exhibited significant circadian variation in the expression of HLA-DR in the proximal airways and CD54 in the distal airways. CONCLUSION: The increased CD51 at night in patients with NA may be related to increased airway inflammation and repair processes in response to injury. The circadian changes in CD54 and HLA-DR in control subjects require further study to determine their significance. (J Allergy Clin 相似文献
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S Kudoh I Komuro Y Hiroi Y Zou K Harada T Sugaya N Takekoshi K Murakami T Kadowaki Y Yazaki 《Canadian Metallurgical Quarterly》1998,273(37):24037-24043
Many lines of evidence have suggested that angiotensin II (AngII) plays an important role in the development of cardiac hypertrophy through AngII type 1 receptor (AT1). To determine whether AngII is indispensable for the development of mechanical stress-induced cardiac hypertrophy, we examined the activity of mitogen-activated protein kinase (MAPK) family and the expression of the c-fos gene as hypertrophic responses after stretching cultured cardiac myocytes of AT1a knockout (KO) mice. When cardiac myocytes were stretched by 20% for 10 min, extracellular signal-regulated protein kinases (ERKs) were strongly activated in KO cardiomyocytes as well as wild type (WT) myocytes. Both basal and stimulated levels of ERKs were higher in cardiomyocytes of KO mice than in those of WT mice. Activation of another member of the MAPK family, p38(MAPK), and expression of the c-fos gene were also induced by stretching cardiac myocytes of both types of mice. An AT1 antagonist attenuated stretch-induced activation of ERKs in WT cardiomyocytes but not in KO cardiomyocytes. Down-regulation of protein kinase C inhibited stretch-induced ERK activation in WT cardiomyocytes, whereas a broad spectrum tyrosine kinase inhibitor (genistein) and selective inhibitors of epidermal growth factor receptor (tyrphostin, AG1478, and B42) suppressed stretch-induced activation of ERKs in KO cardiac myocytes. Epidermal growth factor receptor was phosphorylated at tyrosine residues by stretching cardiac myocytes of KO mice. These results suggest that mechanical stretch could evoke hypertrophic responses in cardiac myocytes that lack the AT1 signaling pathway possibly through tyrosine kinase activation. 相似文献
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