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101.
Masashi Takahashi Shin-Ichi Goto Kazuhisa Mori Izumi Mataga 《Frontiers of Materials Science in China》2008,2(4):437-440
The purpose of this study is to clarify the difference of histology and elemental composition of the cervical enamels among
the human permanent teeth. The reground surfaces at the cervical enamels of them were observed under scanning electron microscopy
(SEM). The contents of seven elements were analyzed quantitatively with electron probe microanalyzer (EPMA). The widths of
the rod sections at the cervical enamels were larger than those at the cuspal enamels. The rod sections at the mesial cervical
enamels in the incisors were more obscure and more decayed by acid solution than those in the premolars and molars. The calcium
and phosphorus contents of the cervical enamels were significantly lower than those of the cuspal enamels. The carbon content
of the cervical enamels was significantly higher than that of the cuspal enamels. The calcium and phosphorus contents of the
cervical enamels were the significantly highest in the premolars. The carbon and sodium contents of the cervical enamels were
significantly highest in the premolars. It is thought that the calcification level is lower, while the content of organic
matter is higher at the cervical enamels than those at the cuspal enamels. It is considered that the sodium causes high calcification. 相似文献
102.
Takashi Kuda Taeko KuniiHideyuki Goto Takamoto SuzukiToshihiro Yano 《Food chemistry》2007,103(3):900-905
Ecklonia stolonifera and Ecklonia kurome are traditional edible brown algae in the fisheries towns in Far East Asia. In the Noto Peninsula area, Ishikawa, Japan, both the Ecklonia are called ‘kajime’ and people believe that the algae improve the property of blood. To determine the varieties of antioxidant and antibacterial properties E. stolonifera and E. kurome products, assays for total phenolic content and antioxidant activities, including DPPH radical-scavenging activity, superoxide anion radical-generated by non-enzymatic system, ferrous-reducing power and WST-8, a tetrazolium salt, redox activity of four dried and two boiled E. stolonifera, and four dried and two raw E. kurome preparations were tested in this study. Furthermore, antibacterial activity of the products was tested. Though the total phenolic content, the antioxidant activity and the antibacterial activities of E. stolorifera and E. kurome products were high, these properties were varied by manufacturers or each product. Especially, two dried and two boiled products of E. stolonifera showed low activities. The results of this study indicate that the contents of functional compounds and their activities were affected or decreased greatly by the processing method. 相似文献
103.
The fundamental modes in an optical waveguide with multiquantum-well structure are analysed by the matrix method. It is found that the separation between the propagation constants of the TE and TM waves is relatively large and that the equivalent planar slab guide approximation is available only for TE waves. 相似文献
104.
TR Kim Y Goto N Hirota K Kuwata H Denton SY Wu L Sawyer CA Batt 《Canadian Metallurgical Quarterly》1997,10(11):1339-1345
Bovine beta-lactoglobulin (BLG) variant A has been expressed in the methylotropic yeast Pichia pastoris by fusion of the cDNA to the sequence coding for the alpha-mating factor prepro-leader peptide from Saccharomyces cerevisiae. P. pastoris Mut+ transformants were obtained by single cross-over integration of the BLG-containing vector into the AOX1 locus. In a fed-batch fermenter, a cell density of approximately 300 mg/ml was achieved by controlled glycerol feeding for a total of 24 h. After 72 h of methanol induction, the secreted BLG reached levels of > 1 g/l. The secreted protein could be purified to homogeneity by ion-exchange chromatography. Amino-terminal sequencing of the secreted BLG revealed that the Glu-Ala spacer repeats inserted between the mature protein and the alpha-factor prepro-leader were still present. The purified protein was characterized by a number of methods, including CD spectroscopy, guanidine-HCl unfolding, crystallization and two-dimensional 1H-NMR spectroscopy. By all of these measures, the physical characteristics of recombinant BLG were indistinguishable from those of the native purified bovine BLG, making it useful as a model for protein folding and other biophysical studies. 相似文献
105.
106.
K Tsukuda Y Suzuki K Kameoka N Osawa Y Goto H Katagiri T Asano Y Yazaki Y Oka 《Canadian Metallurgical Quarterly》1997,14(12):1032-1037
To investigate the prevalence and clinical characteristics of diabetes mellitus caused by mitochondrial gene mutations in the tRNA[Leu(UUR)] region, a known 'hot spot' for pathogenic mutations, we screened 440 diabetic patients with diabetic mothers for 11 mitochondrial gene mutations reported in mitochondrial neuromuscular disorders; nucleotide pairs (np) 3250, 3251, 3252, 3254, 3256, 3260, 3271, 3291, 3302 and 3303 in addition to an A to G transition at np 3243. The dot-blot hybridization method using 32P-labelled sequence-specific oligonucleotides as probes was used. One subject carrying a T to C transition at np 3271 and seven carrying the A to G transition at np 3243 were identified, while none of the other diabetic patients screened had these mutations in the tRNA[Leu(UUR)] region. The patient with the 3271 mutation, a 39-year-old male, had excellent glycaemic control with diet alone and had neither hearing impairment nor symptoms suggesting mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). Thus, among patients with maternally transmitted diabetes, the prevalence of the 3271 mutation was approximately one-seventh that of the 3243 mutation, and other mutations are even more rare in the mitochondrial tRNA[Leu(UUR)] region. 相似文献
107.
Kazuhiro Nagata Katsumi Ohira Hisao Yamada Kazuhiro S. Goto 《Metallurgical and Materials Transactions B》1987,18(3):549-555
The velocity and absorption coefficient of longitudinal ultrasonic waves with 5 and 10 MHz in molten and glassy silicates
and borates have been measured by means of the pulse-echo method in 300 to 1600 K. The silicate and borate were Na2O−SiO2, K2O−SiO2, PbO−SiO2, Na2O−B2O3, and PbO−B2O3. The velocity of sound decreased with increasing temperature and decreased rapidly near the transition temperature of glasses.
The product of the one-third power of velocity of sound and the molar volume of the oxide melt was constant and independent
of temperature. The absorption coefficient of ultrasonic waves in the oxide melts increased with an increase in viscosity.
The absorption mechanisms of ultrasonic waves and the mean free path of phonons in the oxide melts were discussed. 相似文献
108.
Shimizu N. Harada Y. Miyamoto N. Hosoya M. Goto E. 《Electron Devices, IEEE Transactions on》1989,36(6):1175-1181
The fundamental characteristics are described of the quantum flux parametron (QPF), measured by a method in which the output signals of the QFP are detected with a DC SQUID. The DC SQUID linearly and continuously converts the output current of the QFP to voltage, allowing the output signal of the QFP to be measured as the voltage of the DC SQUID. The fundamental characteristics of the QFP have been experimentally confirmed in detail 相似文献
109.
A 6-degrees-of-freedom serial arm hand is controlled to move toward an object in an unseen environment. We developed a consciousness-based
architecture (CBA), which is a hierarchical human development model representing the relationship between consciousness and
behavior and is used for imitating a human groping action. During forward motion toward the object, a robot arm hand can help
to avoid obstacles from which the robot collects contact information. The CBA organizes such information to learn a path plan
for backward motion to the origin without contact with the obstacles. Experimental results show that the CBA successfully
extends the hand to the goal while avoiding any obstacle.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
110.
The influence of HfO2 addition on the fracture strength and microstructure of ß-SiAlON ceramics sintered from Si3 N4 and Al2 O3 powders was investigated. The strength was increased by the addition of HfO2 , from ∼500 MPa to 700 MPa, and was almost constant from ambient temperature to 1300°C. Monoclinic HfO2 grains that were distributed in the SiAlON grain boundaries had a flat shape (∼20 nm thick) and were surrounded by an amorphous phase. The aluminum concentration in ß-SiAlON in the samples with an Al2 O3 starting composition of 15 wt% was decreased by the addition of HfO2 . The amount of secondary phases was very small at grain boundaries between the SiAlON grains; amorphous phases were observed infrequently at the triple points but were very small (∼20 nm). The effects of HfO2 addition on the mechanism of the microstructure development and fracture strength are discussed. 相似文献