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351.
K Kamide H Rakugi M Nagano N Nakano M Ohishi J Higaki T Ogihara 《Canadian Metallurgical Quarterly》1997,20(2):127-132
A simplified method of diagnosing anterior divisional blocks (hemiblocks) at a glance is made possible by using a knowledge of the lead line directions on a hexaxial system. The term 'divisional block' is preferred to 'hemiblock' because a block of one of the three divisions of the left bundle cannot be a hemiblock. The diagnosis of an anterior divisional block can be simplified by utilization of the concept that it is mainly a terminal conduction abnormality in the frontal plane with a direction between -60 degree and -90 degree. Using a hexaxial system the diagnosis can be quickly made regardless of axis by simply noting the presence of a terminal negativity (S wave) in aVF, terminal positivity in aVR (R or R'), and no S in lead 1. 相似文献
352.
H Oishi T Sasaki F Nagano W Ikeda T Ohya M Wada N Ide H Nakanishi Y Takai 《Canadian Metallurgical Quarterly》1998,273(51):34580-34585
The Rab3 small G protein subfamily (Rab3) consists of four members, Rab3A, -B, -C, and -D. We have recently isolated and characterized the Rab3 regulators, GDP/GTP exchange protein (GEP) and GTPase activating protein (GAP), both of which are specific for the Rab3 subfamily. Rab3 GEP stimulates the conversion of the GDP-bound inactive form to the GTP-bound active form, whereas Rab3 GAP stimulates the reverse reaction. Of the four members of the Rab3 subfamily, evidence is accumulating that Rab3A is involved in Ca2+-dependent exocytosis, particularly in neurotransmitter release. We first analyzed the subcellular localization of Rab3 GEP and GAP in rat brain. Subcellular fractionation analysis showed that both Rab3 GEP and GAP were enriched in the synaptic soluble fraction. Immunocytochemical analysis in primary cultured rat hippocampal neurons showed that both Rab3 GEP and GAP were concentrated at the presynaptic nerve terminals. We then examined whether Rab3 GEP and GAP were involved in Ca2+-dependent exocytosis by use of human growth hormone (GH) co-expression assay system of cultured PC12 cells. Overexpression of the deletion mutant of Rab3 GEP possessing the catalytic activity reduced the high K+-induced GH release without affecting the basal GH release, whereas that of the deletion mutant lacking the catalytic activity showed no effect on the high K+-induced GH release. In contrast, overexpression of Rab3 GAP or its deletion mutant possessing the catalytic activity did not affect the high K+-induced GH release or the basal GH release. These results indicate that Rab3 GEP and GAP are colocalized with Rab3A at the synaptic release sites and suggest that they regulate the activity of Rab3A and are involved in Ca2+-dependent exocytosis. 相似文献
353.
Yutaka Kuroyama Shigeru Itoh Zhi-yue Liu Hiroshi Kitaki Shiro Nagano Kenji Itoh 《Metals and Materials International》1998,4(4):808-811
A new method was devised to generate an ultra-high dynamic pressure for materials synthesis and phase transformation by using the cylindrical explosion. Unlike the ordinary cylindrical method, the specimen is not directly packed into the metal tube but sandwiched between the metal films that are rolled into a cylindrical geometry. For distinguishable point of view, we term it as ’rolled-film’ method. The numerical simulation demonstrates that this method can produce higher shock pressure than the ordinary cylindrical method. The practical experiment for boron nitride phase transformation also indicates thal a higher shock pressure is able to be achievable. 相似文献
354.
With jumping mechanisms,soft landing motion is important to protect loads and the mechanisms.This study proposes a leg mechanism for soft landing based on biological motion.Human jumping motion with a load suggests a unique motion for soft landing.The landing model consists of two periods.Jerk is minimized in the first period and force is minimized in the second period.In comparison with other landing models,this model is specialized for soft landing motion protecting an objective part.Given all mechanisms ... 相似文献
355.
An underground structure buried in a soft ground located in a seismic-active region may experience intolerable deformation due to earthquake loading. The collapse of Daikai Station of the Kobe subway line during the 1995 Hyogoken-Nambu Earthquake demonstrated that underground structures may also sometimes be at high risk for failure in a huge earthquake. In particular, box culverts constructed in a soft ground with a thin overburden are vulnerable to earthquakes. Some previously constructed box culverts do not meet the present requirements of seismic design standards. In this paper, numerical analyses and 1-g shaking table tests are conducted to evaluate the effect of partial ground improvement (PGI) as a seismic countermeasure for the above-mentioned existing box culverts. Particular attention is paid to the optimum pattern of PGI that can most efficiently reduce the impact of an earthquake on a box culvert. The underground structure of Daikai Station is taken as an example and its physical and geometric conditions are used to model the box culvert in the analyses and the tests. In order to accurately consider the influence of the soil-structure interaction (SSI) on the underground structures, both the soil and the box culvert are considered in the analyses and the shaking table tests. Four different patterns of PGI are considered. Based on the analyses and the tests, an optimum pattern for the PGI of existing box culverts is proposed. 相似文献
356.
Yoshihiro Takao Hiroshi Kudo Junichi Mitani Yoshiyuki Kotani Satoshi Yamaguchi Keizaburo Yoshie Kazuo Sukegawa Nobuhisa Naori Satoru Asai Michiari Kawano Takashi Nagano Ikuhiro Yamamura Masaya Uematsu Naoki Nagashima Shingo Kadomura 《Microelectronics Reliability》2002,42(1)
This paper describes a 0.11 μm CMOS technology with high-reliable copper (Cu) and very low k (VLK) (k<2.7) interconnects for high-performance and low-power applications of a 0.13 μm generation. Aggressive design rules, 0.11 μm gate transistor and 2.2 μm2 six-transistor SRAM cell are realized by using KrF 248 nm lithography, optical proximity effect correction, and gate-shrink techniques. Eight-level interconnects are fabricated with seven level of Cu/VLK interconnect and one level of Al/SiO2 interconnect. Drain current of 0.67 and 0.28 mA/μm are realized for nMOSFET and pMOSFET with 0.11 μm gate, respectively. Propagation delay of two input NAND with the Cu/VLK interconnect is estimated. The delay is improved by more than 70%, compared to 0.18 μm CMOS technology with Cu/FSG interconnects. Functional 288 kbit SRAM circuit is demonstrated with 2.2 μm2 cell and Cu/VLK interconnect. 相似文献
357.
Inaba S. Miyano K. Nagano H. Hokazono A. Ohuchi K. Mizushima I. Oyamatsu H. Tsunashima Y. Ishimaru K. Toyoshima Y. Ishiuchi H. 《Electron Devices, IEEE Transactions on》2004,51(9):1401-1408
In this paper, novel channel and source/drain profile engineering schemes are proposed for sub-50-nm bulk CMOS applications. This device, referred to as the silicon-on-depletion layer FET (SODEL FET), has the depletion layer beneath the channel region, which works as an insulator like a buried oxide in a silicon-on-insulator MOSFET. Thanks to this channel structure, junction capacitance (C/sub j/) has been reduced in SODEL FET, i.e., C/sub j/ (area) was /spl sim/0.73 fF//spl mu/m/sup 2/ both in SODEL nFET and pFET at Vbias =0.0 V. The body effect coefficient /spl gamma/ is also reduced to less than 0.02 V/sup 1/2/. Nevertheless, current drives of 886 /spl mu/A//spl mu/m (I/sub off/=15 nA//spl mu/m) in nFET and -320 /spl mu/A//spl mu/m (I/sub off/=10 nA//spl mu/m) in pFET have been achieved in 70-nm gate length SODEL CMOS with |V/sub dd/|=1.2 V. New circuit design schemes are also proposed for high-performance and low-power CMOS applications using the combination of SODEL FETs and bulk FETs on the same chip for 90-nm-node generation and beyond. 相似文献
358.
Imazono T Koike M Kawachi T Hasegawa N Koeda M Nagano T Sasai H Oue Y Yonezawa Z Kuramoto S Terauchi M Takahashi H Handa N Murano T Sano K 《Applied optics》2012,51(13):2351-2360
Laminar and blazed type holographic varied-line-spacing spherical gratings for use in a versatile soft x-ray flat-field spectrograph attached to an electron microscope are designed, fabricated, and evaluated. The absolute diffraction efficiencies of laminar (or blazed) master and replica gratings at 86.00° incidence evaluated by synchrotron radiation show over 5% (or 8%) in the 50-200 eV range with the maxima of 22% (or 26%-27%). Also the resolving power evaluated by a laser produced plasma source is in excess of 700 at the energy near the K emission spectrum of lithium (~55 eV) for all gratings. Moreover, the K emission spectrum of metallic Li with high spectral resolution is successfully observed with the spectrograph attached to a transmission electron microscope. 相似文献
359.
360.
Shigeru Itoh Shiro Nagano Masahiro Fujita Tsutomu Takano Ryouzou Honda Motoyosi Ikeda 《Metals and Materials International》1998,4(4):843-846
Sugi (Cryptomeria japonica D.Don) wood generally has the so-called black heartwood, which contains the extremely high moisture content. Although subjected to the drying process, it is difficult to be dried up completely so that Sugi wood does not have the sufficient strength for use. The reason is that during drying process, the bordered pit membrane on traicheids closes faster near the heartwood in Sugi wood so that the internal moisture is not easily come out to the outside. At the mean time, it also makes very difficult to saturate the rotten-proof chemicals into the dried Sugi wood to have it become an additionally valuable wood. In this paper, we will develop an underwater shock wave technique to treat the pre-dried wood for the improvement of the drying property as well as the permeability and strength of Sugi wood by selectively fracturing the bordered pit membrane. The result indicates a very remarkable improvement on the drying time. The mechanism of the fracture of the bordered pit by underwater shock wave will be further studied in the future. 相似文献