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991.
A noninvasive method was developed for measuring the digital arterial pressure and the compliance by using a fingertip pneumoplethysmograph and a pneumatic cuff. The compliance (C) of the digital artery was obtained from the peak amplitude of the volume pulse wave (deltaVp-a) under the effect of the cuff pressure (Po-a) by the equation: C = deltavp-a/(Ps - P-o-a) during the dicrotic phase defined in this study. The normal mean value was 11.37 +/- 0.59 X 10(-5) cm3/mmHg. On lowering of the cuff pressure, the moment when the deltaVp value becomes positive is regarded as the systolic pressure (Ps). At the end of the dicrotic phase, the mean amplitude (deltaVss') of the pulse wave during one pulse cycle (SS') and the ratios (deltaVss'/deltaVsd), where deltaVsd is the mean amplitude of the wave during the systolic period (SD), of successive waves after a particular wave fail to increase at the same rate when the cuff pressure decreased below the diastolic pressure. The cuff pressure corresponding to this particular wave is regarded as the diastolic pressure (Pd). The mean value of the mean digital pressure of normotensive subjects was 80.6 +/- 1.2 mmHg. 相似文献
992.
993.
Resuspension of bottom sediment by an internal wave in Lake Biwa 总被引:2,自引:0,他引:2
Yuji Sakai Jun Murase Atsuko Sugimoto Kenji Okubo Eiichiro Nakayama 《Lakes & Reservoirs: Research and Management》2002,7(4):339-344
An internal wave‐induced resuspension of bottom sediment and resultant changes in water chemistry were investigated in the sublittoral area of Lake Biwa in the late stage of the stagnant period. The thermocline was measured at between depths of 15 and 20 m at the beginning of the observation and rapidly dropped by 5 m within 3 h. The downward movement of the thermocline resulted in markedly increased turbidity at the top of the thermocline (20 m in water depth). Concentrations of dissolved methane synchronistically increased with turbidity, especially in the top of the thermocline where there was the highest turbidity. Total dissolved phosphorus and particulate phosphorus also increased in the thermocline. In contrast, the soluble reactive phosphate concentration decreased with time. An increase in the concentrations of particulate metals (aluminium, iron and titanium), which probably originated from mineral particles, was more marked in the water sample collected at 1 m above the bottom than at the peak of turbidity. The results indicated that an internal wave caused resuspension of the bottom sediment and also affected the water chemistry. 相似文献
994.
The present analysis investigates non-Darcy forced convective heat transfer in a channel confined by two parallel walls subjected to uniform heat flux in a highly porous medium saturated with a non-Newtonian power-law fluid. Extensive numerical integrations have been carried out utilizing the Brinkman-Forchheimer extension of the Darcy model in order to study the effects of pseudoplasticity, and Brinkman and Forchheimer terms on the heat transfer characteristics. 相似文献
995.
Yuki KimuraChihiro Kaito Katsumi HanamotoMuneo Sasaki Seiji KimuraToshitaka Nakada Yoshio SaitoYasuyuki Nakayama 《Carbon》2002,40(7):1043-1050
Growth of small carbyne crystals in a thin amorphous carbon film has been observed by high-resolution transmission electron microscopy (HRTEM). The as-deposited film was composed of diamond and graphite crystallites of size 1 nm. Circular α-phase carbyne crystals predominantly grew to 20 nm in size and transformed into (α+β)-phase crystals with an elongated shape of 100 nm in length. The typical correlation during the transformation is (220)α//(301)(α+β). The c-axes of both grown crystals were oblique to the direction of the electron beam. The growth process of carbyne crystals will be discussed in terms of selective excitation of graphite crystallites by an SR beam. 相似文献
996.
A rare case of left atrial free floating ball thrombus with mitral stenosis is reported. A 66-year-old woman was admitted for epigastralgia and acute heart failure without atrial fibrillation and previous embolization. The patient was treated successfully with removal of ball thrombus and mitral valve replacement. Intraoperative transesophageal echocardiography was effective for monitoring of mobile left atrial thrombus. 相似文献
997.
To make starch/polycaprolactone (PCL) blend with high miscibility, starch was chlorinated (starch‐Cl) by using methanesulfonylchloride (CH3SO2Cl) in dimethylformamide (DMF) prior to blending. Starch‐Cl/PCL blends were prepared by the mixing between starch‐Cl and PCL solutions under various conditions. To study the change of structure, thermal and physical characteristics of starch‐Cl/PCL blend, FTIR, DSC, SEM, and solvent resistance were measured. By blending starch‐Cl and PCL, a chemical reaction occurred partially in blend (FTIR result); thereby, the miscibility (DSC and SEM results) and solvent resistance were increased. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1716–1723, 2004 相似文献
998.
999.
B-ISDN multimedia communication and collaboration platform usingadvanced video workstations to support cooperative work 总被引:1,自引:0,他引:1
Hoshi T. Mori K. Takahashi Y. Nakayama Y. Ishizaki T. 《Selected Areas in Communications, IEEE Journal on》1992,10(9):1403-1412
A distributed real-time computer-supported cooperative work (CSCW) platform called the B-ISDN group teleworking system is described. The system combines the high-speed multimedia communication capability with advanced video integrated workstations. The aim of this system is to support ad hoc meetings and real-time collaborative work between small groups of people who are geographically distributed. The main features of the system are face-to-face communication and the capability for sharing and comanipulating shared multimedia information including video. The concept and architecture of the system are described. A prototype group teleworking system that uses B-ISDN multimedia workstations is also described. A mock remote medical consultation application for the system is presented 相似文献
1000.