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排序方式: 共有2367条查询结果,搜索用时 15 毫秒
971.
In Vitro and In Vivo Digestibility of Recrystallized Amylose and Its Application for Low Glycemic Foods 总被引:1,自引:0,他引:1
Tatsuya Morita Junya Hayashi Hirofumi Motoi Takahiro Yagishita Koji Takeya Kimio Sugiyama Shuhachi Kiriyama 《Journal of food science》2005,70(3):S179-S185
ABSTRACT: To predict physiologic functions of recrystallized amylose (RCA), the true resistant starch (RS) content of RCA in the small intestine was directly measured using ileorectostomized rats where the distal ileum was anastomosed to the rectum (the cecum and colon were surgically resected together). The estimated in vivo resistant starch content of RCA was the same as the value obtained from the in vitro enzymatic RS determination (∼50%). RCA resistance to amylolytic enzymes in the small intestine was retained even after RCA incorporation into processed foods, and a bread containing 20% RCA showed a significantly lower glycemic response in rats compared with that of a control bread. Also, RCA ingestion significantly and dose-dependently decreased the body fat accretion and lowered serum concentrations of cholesterol and triglycerides in rats compared with cornstarch. These lipid-lowering effects of RCA were comparable to those obtained with high-amylose cornstarch. The restricted energy value as well as suppressed insulin response with RCA ingestion might be related to preferable changes in lipid metabolism. These nutritional properties of RCA may suggest a possible benefit as an alternative source of resistant starch for preventing diabetes, hyperlipidemia and obesity, and so on. 相似文献
972.
Kawaguchi M. Gouardes E. Schlenker D. Kondo T. Miyamoto T. Koyama F. Iga K. 《Electronics letters》2000,36(21):1776-1777
A metal organic chemical vapour deposition grown GaInNAs quantum well laser emitting at 1.25 μm is reported. The lowest threshold current density obtained by 50 μm wide stripe lasers was 340 A/cm2 for a cavity length of 1420 μm. Which is almost comparable to the lowest value reported for GaInNAs lasers grown by molecular beam epitaxy. The threshold current density per well was 170 A/cm2, which is the lowest threshold value reported to date 相似文献
973.
Takeyasu Saito Yoshihisa Hirata Mariko Oyanagi Naoki Okamoto Kazuo Kondo 《Materials Letters》2011,65(17-18):2826-2828
ZnO thin films were formed in a solution with Zn(NO3)2 and Dimethylaminoborane at 70 °C. The effects of the aluminum ion concentration in the aqueous solution on the surface morphology, crystallographic structure and growth rate were investigated. By adding 10? 4 mol/l of Al, the growth rate was enhanced from 0.13 to 0.35 μm/h. In addition, the surface morphology became flat when the appropriate amount of Al(NO3)3, i.e., 10? 4 mol/l, was added. The Ra and Rz decreased from 20–32 nm and 115–145 nm to 1–11 nm and 7–60 nm, respectively. 相似文献
974.
Taniguchi S. Mochiduki S. Yamakawa T. Wakao S. Kondo K. Yoneyama T. 《Industry Applications, IEEE Transactions on》2009,45(1):194-202
This paper investigates a starting procedure of rotational sensorless permanent magnet synchronous motor (PMSM) in the rotating condition, which is suitable for some applications with higher maximum rotor frequency and longer current sampling time. Instantaneous estimation of initial rotor position and frequency, right after gates start, is essential for restarting the operation of inverters. Existing estimation methods are not available for the aforementioned applications because of their higher maximum rotor frequency and longer current sampling time. To cope with this problem, we propose a novel initial rotor frequency estimation method. The proposed estimation method is verified by experiments using a 2-kW interior PMSM and a numerical simulation. 相似文献
975.
Takaaki Fukui Nobuto Kitamura Takayuki Kurokawa Masashi Yokota Eiji Kondo Jian Ping Gong Kazunori Yasuda 《Journal of materials science. Materials in medicine》2014,25(4):1173-1182
Implantation of PAMPS/PDMAAm double-network (DN) gel can induce hyaline cartilage regeneration in the osteochondral defect. However, it is a problem that the volume of the regenerated cartilage tissue is gradually reduced at 12 weeks. This study investigated whether intra-articular administration of hyaluronic acid (HA) increases the volume of the cartilage regenerated with the DN gel at 12 weeks. A total of 48 rabbits were used in this study. A cylindrical osteochondral defect created in the bilateral femoral trochlea was treated with DN gel (Group DN) or left without any implantation (Group C). In both Groups, we injected 1.0 mL of HA in the left knee, and 1.0 mL of saline solution in the right knee. Quantitative histological evaluations were performed at 2, 4, and 12 weeks, and PCR analysis was performed at 2 and 4 weeks after surgery. In Group DN, the proteoglycan-rich area was significantly greater in the HA-injected knees than in the saline-injected knees at 12 weeks (P = 0.0247), and expression of type 2 collagen, aggrecan, and Sox9 mRNAs was significantly greater in the HA-injected knees than in the saline-injected knees at 2 weeks (P = 0.0475, P = 0.0257, P = 0.0222, respectively). The intra-articular administration of HA significantly enhanced these gene expression at 2 weeks and significantly increased the volume of the hyaline cartilage regenerated by implantation of a DN gel at 12 weeks. This information is important to develop an additional method to increase the volume of the hyaline cartilage tissue in a potential cartilage regeneration strategy using the DN gel. 相似文献
976.
Yasuhiko Iwasaki Jun-ichi Kondo Akinori Kuzuya Rui Moriyama 《Science and Technology of Advanced Materials》2016,17(1):285-292
Specific detection of protein biomarkers plays an important role in diagnostics and therapeutics. We have fabricated polymeric nanogels, which can specifically interact with the cancer biomarker thrombin to serve as a model. Two types of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymers bearing a thrombin-binding oligonucleotide aptamer and its complementary chain were independently synthesized by redox-initiated radical polymerization. These MPC polymers associate in a complimentary fashion due to double strand formation of the oligonucleotides in aqueous media, leading to the spontaneous formation of spherical nanogels. Nanogel formation was confirmed by dynamic light scattering (DLS) and transmittance microscopy. The average size of nanogel particles was 124 ± 2 nm and the nanogels were mono-dispersed (polydispersity index 0.21). Functional intercalators could be stably incorporated into nanogels through the physical interaction between the intercalators and the oligonucleotides. The ethidium bromide (EtBr)-incorporating nanogels were used as detectors for thrombin. The fluorescence intensity of solutions containing the EtBr-incorporating nanogels was decreased with an increase in the concentration of thrombin. The transformation of quadruplex–thrombin structure from complementary double-stranded structures resulted in the decrease in fluorescence intensity. In contrast, the intensity did not change when the nanogels were incubated with albumin. Thrombin is only one such model used to demonstrate this technique; oligonucleotide aptamers can be freely designed to interact with versatile bio-substances. Therefore, aptamer-crosslinked nanogels can be appropriate nanomaterials for disease diagnosis and therapy. 相似文献
977.
978.
Teruyuki Nakato Sae Inoue Yuuki Hiraragi Jun Sugawara Emiko Mouri Hirofumi Aritani 《Journal of Materials Science》2014,49(2):915-922
Binary colloids of inorganic nanosheets prepared by exfoliation of two different layered crystals form phase-separated structures with demixing of the two nanosheets. The phase-separated colloids of photocatalytic niobate and photochemically inert clay nanosheets exhibit unusual photochemical reactions based on the phase-separated structure. The present paper reports photocatalytic decomposition of a cyanine dye in this binary colloid, where the dye is selectively adsorbed on the clay nanosheets to be spatially separated from the photocatalytic nanosheets. Upon UV irradiation, the dye is photocatalytically decomposed in the colloids containing the niobate nanosheets, but self-photolysis of the dye is observed in the colloid lacking the photocatalytic nanosheets. Faster decomposition in nitrogen than in air suggests contribution of the conduction-band electrons generated in the niobate nanosheets to the photocatalytic reaction. In the binary colloid, the degradation is retarded compared with the single-component niobate colloid. Larger clay content more stabilized the dye against the decomposition. In contrast, irradiation of the colloids with visible light causes self-photolysis of the dye even in the presence of the niobate nanosheets, indicating the absence of electron transfer from the photoexcited dye to the photocatalytic nanosheets. 相似文献
979.
Yasushi Ito Tomomitsu Hori Tsuneo Kusunoki Hiroshi Nomura Hirofumi Kondo 《Journal of the Society for Information Display》2014,22(8):419-428
SrGa2S4:Eu and CaS:Eu phosphors are useful to provide a wider color gamut to LCDs since their emissions are narrower, but they easily react with moisture. The phosphor sheet containing them was developed. The moisture barrier layers on it can separate them from a humid atmosphere. The LCD with the phosphor sheet could realize the wider color gamut of 90% NTSC‐xy, while the color gamut of the original LCD with the white LEDs containing YAG:Ce phosphor was 71% NTSC‐xy. The improvement of the brightness of the LCD with the phosphor sheet was studied. Encapsulates with a greater curvature on blue LEDs used with the phosphor sheet can increase the brightness. The brightness of the LCD with the phosphor sheet and blue LEDs with the spherical encapsulates of which the curvature = about 0.7 was estimated to reach to 85% of that of the original LCD. The simpler phosphor sheet with the aluminum film edge seals was also developed. It was confirmed that it has sufficient reliability during storage and operation at high temperature and high humidity and there is no difference in its reliability between the edge area and the center area. The importance of the moisture barrier layers which protect the SrGa2S4:Eu and CaS:Eu phosphors was confirmed. The phosphor sheet with the moisture barrier layers had better reliability than that with the PET layers. 相似文献
980.
This paper discusses power flow analysis and DC capacitor voltage regulation of a modular multilevel cascaded converter (MMCC) based on double‐star chopper cells (DSCC). This analysis reveals the relationship between the circulating current through the DC link and the average power flowing out of or into each chopper cell. The DC component of the circulating current supplies half the active output power to the upper and lower strings of the chopper cells, while in contrast the fundamental frequency component transfers an amount of power between the upper and lower strings. Thus, the MDCC–DSCC can balance the capacitor voltages among the cells by controlling the amplitude of the fundamental frequency component of the circulating current. A new control method based on power flow analysis is employed, and its effectiveness is verified by circuit simulation. 相似文献