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51.
T Osada T Katsumura T Hamaoka S Inoue K Esaki A Sakamoto N Murase J Kajiyama T Shimomitsu H Iwane 《Canadian Metallurgical Quarterly》1999,86(2):709-719
The redistribution of blood flow (BF) in the abdominal viscera during right-legged knee extension-flexion exercise at very low intensity [peak heart rate (HR), 76 beats/min] was examined by using Doppler ultrasound. While sitting, subjects performed a right-legged knee extension-flexion exercise every 6 s for 20 min. BF was measured in the upper abdominal aorta (Ao), right common femoral artery (RCFA), and left common femoral artery (LCFA). Visceral BF (BFVis) was determined by the equation [BFAo - (BFRCFA + BFLCFA)]. A comparison with the change in BF (DeltaBF) preexercise showed a greater increase in DeltaBFRCFA than in DeltaBFAo during exercise. This resulted in a reduction of BFVis to 56% of its preexercise value or a decrease in flow by 1,147 +/- 293 (+/-SE) ml/min at the peak workload. Oxygen consumption correlated positively with DeltaBFAo, DeltaBFRCFA, and DeltaBFLCFA but inversely with DeltaBFVis during exercise and recovery. Furthermore, BFVis (% of preexercise value) correlated inversely with both an increase in HR (r = -0.89), and percent peak oxygen consumption (r = -0.99). This study demonstrated that, even during very-low-intensity exercise (HR <90 beats/min), there was a significant shift in BF from the viscera to the exercising muscles. 相似文献
52.
Atomic force microscopy of histological sections using a new electron beam etching method 总被引:2,自引:0,他引:2
In order to examine histological sections of the rat vomeronasal epithelium with the atomic force microscope (AFM), we developed an electron beam etching method that improves the resolution of AFM images. This method results in AFM images comparable to those obtained with the transmission electron microscope (TEM). Ultrathin tissue sections embedded in epoxy resin were observed before and after the treatment with electron beam radiation. Before electron beam treatment, epithelial structures such as the microvilli surface, dendritic processes, the supporting cell layers and the neuronal cell layers were all visible using the AFM. However, only a few subcellular structures could also be resolved. The AFM images were not as clear as those obtained with the TEM. After electron beam treatment, however, the resolution of AFM images was greatly improved. Most of the subcellular structures observed in TEM images, including the inner membrane of mitochondria, ciliary-structure precursor body, junctional complexes between the neurons and supporting cells, and individual microvilli were now visible in the AFM images. The electron beam treatment appeared to melt the embedding resin, bringing subcellular structures into high relief. The result of this study suggests that electron beam etching of histological samples may provide a new method for the study of subcellular structure using the AFM. 相似文献
53.
54.
In this study we propose a design for an LSI circuit that implements a cellular automaton. The cellular automaton is a parallel and distributed architecture device suitable for high‐speed image processing. To develop a cellular automaton LSI circuit, it is necessary to design small‐size unit cell circuits that can operate according to cell–cell interaction rules. We propose to use νMOSFET devices for such cell circuits. Template matching is implemented by combining multiple input νMOSFET circuits and inverters. A cell circuit was designed for image thinning and shrinking, and its operation was analyzed using a circuit simulator. It was demonstrated that high speed operation (up to 100 MHz clock frequency) can be obtained. © 1999 Scripta Technica, Electr Eng Jpn, 126(3): 41–48, 1999 相似文献
55.
We have developed a method to detect specific proteins with a high sensitivity using a gel electrophoresis method and force measurement of atomic force microscopy (AFM). Biotinylated proteins were separated by electrophoresis and fixed with cross-linking chemicals on the gel, followed by direct force measurement between the biotinylated proteins on the gel and a streptavidin-modified tip of an AFM cantilever. We were able to achieve a high enough sensitivity to detect the picogram order of the biotinylated proteins by evaluating the frequency of the interaction force larger than 100 pN in the force profile, which corresponds to the rupture force of interaction between streptavidin and biotin. 相似文献
56.
Umemura T Hotta H Abe T Takahashi Y Takiguchi H Uehara M Odake T Tsunoda K 《Analytical chemistry》2006,78(21):7511-7516
A sensitive and fast-responsive evanescent wave absorption sensor has been constructed for pH measurements in highly acidic ranges. This sensor is based on a pH-dependent color change of protoporphyrin IX (PPIX). For the sensitive detection, a visible attenuated total reflection spectrometer with a slab optical waveguide (SOWG) was laboratory-made, and the guiding layer surface was modified with a PPIX-immobilized acrylamide-based thin membrane. The sensing membrane with a thickness of approximately 1 mum was directly fabricated on the SOWG glass surface by copolymerization of acrylamide, N,N'-methylene bisacrylamide, and PPIX in the narrow space confined by a cover plate. PPIX possesses two double bonds in its structure, and so it can be covalently incorporated into the membrane. The response characteristics of the PPIX-immobilized optode membrane were explored using aqueous solutions with different concentrations of HNO(3) or HCl. The optode membrane provided characteristic Soret band absorption spectra depending on the hydrogen ion concentration; the absorbance at 410 nm increased with increasing the concentrations in the range of 0.15-2 M, corresponding to the range of pH -0.3 to 0.8. The absorption signal reached 90% of its final value within 10 s, while the absorption signal was quite readily returned to background level simply by passing 2 mL of distilled water through a flow cell with a volume of 16.5 muL placed on the SOWG. Due to the rapid response and reversibility, this sensor could be operated in a flow-through mode as well as in a conventional static mode, where deionized water was conveniently used as a carrier and conditioning solution. In terms of the stability and precision, this sensor showed no significant change in response even after 100 assays and after being stored in a dry condition for over 6 months. Relative standard deviations for 10 replicate measurements were less than 1.8% in the linear range, and the detection limit calculated from 3 times of the standard deviation was 0.02 pH unit. 相似文献
57.
Yagai S Seki T Murayama H Wakikawa Y Ikoma T Kikkawa Y Karatsu T Kitamura A Honsho Y Seki S 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(23):2731-2740
Extremely long nanofibers, whose lengths reach the millimeter regime, are generated via co-aggregation of a melamine-appended perylene bisimide semiconductor and a substituted cyanurate, both of which are ditopic triple-hydrogen-bonding building blocks; they co-aggregate in an unexpected stoichiometrically mismatched 1:2 ratio. Various microscopic and X-ray diffraction studies suggest that hydrogen-bonded polymeric chains are formed along the long axis of the nanofibers by the 1:2 complexation of the two components, which further stack along the short axis of the nanofibers. The photocarrier generation mechanism in the nanofibers is investigated by time-of-flight (TOF) experiments under electric and magnetic fields, revealing the birth and efficient recombination of singlet geminate electron-hole pairs. Flash-photolysis time-resolved microwave conductivity (FP-TRMC) measurements revealed intrinsic 1D electron mobilities up to 0.6 cm(2) V(-1) s(-1) within nanofibers. 相似文献
58.
59.
Aritomo Yamaguchi Norihito Hiyoshi Osamu Sato Mitsumasa Osada Masayuki Shirai 《Catalysis Letters》2008,122(1-2):188-195
Lignin gasification in supercritical water over charcoal supported ruthenium trivalent salts was studied using a batch reactor
at 673 K. Ruthenium (III) nitrosyl nitrate on charcoal (Ru(NO)(NO3)3/C) was more active than ruthenium (III) chloride on charcoal (RuCl3/C) for the gasification reaction. EXAFS analysis revealed that ruthenium metal particles were formed in both RuCl3/C and Ru(NO)(NO3)3/C catalysts during the lignin gasification and that the size of ruthenium metal in Ru(NO)(NO3)3/C was smaller than that in RuCl3/C. It was concluded that well-dispersed ruthenium metal particles were active for the lignin gasification in supercritical
water. 相似文献
60.
Masatoshi Sakairi Fumihito Sato Yoshihito Gotou Koji Fushimi Tatsuya Kikuchi Hideaki Takahashi 《Electrochimica acta》2008,54(2):616-622
A new method for maskless fabrication of metallic patterns or structures on metals is described. A solution flow type droplet cell, with co-axial dual capillaries was applied to form fine metal structures such as strips and rods. This type of droplet cell enables movement of the cell during formation. Nickel fine patterns with a width of about 200 μm were formed on a Cu substrate. The width of the formed pattern does not change with the scanning speed of the cell, but the thickness of the formed pattern changes with the speed. Two different deposition modes were examined to form metal rods, one is a mold free deposition mode and the other is a mold assisted deposition mode. Both modes enable the formation of Ni rods, however, reproducibility of mold free deposition mode was not good. The mold assisted deposition mode has far better the reproducibility, because of the use of the inside wall of the 100 μm diameter inner tube as the mold. It is possible to form nickel micro-rods, about 100 μm in diameter and 12 mm long with relatively smooth surfaces by the mold assisted deposition mode. 相似文献