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71.
The phase equilibrium was quantitatively investigated by using a typical rodlike polymer, poly(p-phenyleneterephthalamide), in mixed solvent system. The experimental results may afford a basis on the formation of liquid crystal of the polymer. 相似文献
72.
A.C. Shaw has introduced the concept of the flow expression which is an extended regular expression and state several results with some conjectures. His conjecture that the flow expressions define context-sensitive languages has been answered negatively by two of the present authors, that is, the flow languages are recursively enumerable.In this paper, it is shown that flow languages for some restricted class of flow expressions are equivalent to Petri net languages. Some related decision problems for flow expressions are also discussed. 相似文献
73.
K Miyahara K Yasuura Y Miyata A Seki H Okamoto T Asakura M Murase 《Canadian Metallurgical Quarterly》1998,46(11):1105-1111
From January 1987 through June 1992, 18 patients with poor left ventricular function (left ventricular ejection fraction [LVEF] less than 0.3) underwent elective isolated primary coronary artery bypass surgery. The mean age was 56.4 years (range, 46 to 72 years), and 15 were males and 3 were females. Mean pre-operative LVEF measured by ventriculography was 0.26 +/- 0.03 (range, 0.19 to 0.30). Sixteen patients (88.9%) had a prior myocardial infarction and 9 (50%) had a history of congestive heart failure. Complete revascularization was the goal for all patients, and the mean number of bypass grafts was 3.0 +/- 0.8 per patient. The left anterior descending coronary artery (LAD) was revascularized in all patients. There were no operative deaths. Post-operative LVEF improved significantly from 0.26 +/- 0.03 to 0.42 +/- 0.11 (p = 0.0002), and the regional left ventricular wall motion improved in the diaphragmatic and posterobasal regions (p < 0.01). The patency of the grafts was 93.9% in all, and 100% for LAD. The mean follow-up period was 77 months, and the overall actuarial survival rate was 88.9% at 10 years. During follow-up periods, two patients died of congestive heart failure (CHF), and two required three rehospitalizations because of CHF. The overall cardiac event free rate was 75.8% at 10 years. In patients with poor left ventricular function, surgical revascularization can be performed safely, but congestive heart failure sometimes occurs during follow-up periods and may be the cause of death. Therefore alternate forms of therapy such as cardiac transplantation and/or TMLR should be considered in selected patients. 相似文献
74.
Toshikazu Takigawa Hidenori Kadoya Takashi Miki Takashi Yamamoto Toshiro Masuda 《Polymer》2006,47(13):4811-4815
Dynamic viscoelastic properties of a series of cyclic olefin copolymers have been investigated. The specimens differ in total molecular weight as well as molecular weight between entanglements. The angular frequency (ω) dependence curves of dynamic storage and loss moduli (G′ and G″, respectively) of the specimens have shown that G′ ∝ ω2 and G″ ∝ ω in the terminal region, and a plateau region at high ω. On the basis of the experimental results, the dependence of total molecular weight as well as molecular weight between entanglements has been examined for zero-shear viscosity (η0) and steady-state compliance (Je). It is shown that for the melts of the copolymers in the entangled regime, Mw being the weight-average molecular weight and Me the molecular weight between entanglements. The steady-state compliance Je for the melts scales with Me and Mw as . 相似文献
75.
Jarmila Jeleníková Petr Pipek Mitsuoshi Miyahara 《European Food Research and Technology》2008,227(4):989-994
A study was conducted to evaluate the influence of breed and sex of animals on tenderness of pork. For evaluation, carcasses
of pure breed barrows and gilts of Large White, Czech pig meat, Landrace and Duroc were used. For laboratory investigations,
the samples of musculus longissimus lumborum et thoracis (20 mm thick) were taken from the same place, at the first cruciate vertebra 48 h post mortem. Seven days post mortem, the
texture of heat-processed meat was measured objectively by the shear method on Instron equipped with Warner–Bratzler shear
device. Meat tenderness and juiciness were also evaluated sensorially. It was observed that the tenderness of cooked meat
is influenced by breed (the tenderest meat was from Duroc breed). The sex of animals has significant effect on meat tenderness
too. At the same time, the effects of pH 45 minutes (pH45) and 24 hours (pH24) post mortem and intramuscular fat content on meat tenderness were evaluated. Correlations were found between shear force
(tenderness) and intramuscular fat content and also between shear force and pH value 45 min post mortem. The shear force decreased
with increasing intramuscular fat content and with increasing pH45 value. Sensory evaluation of tenderness confirmed the objectively measured data. 相似文献
76.
Gaowa Bai Daisuke Furushima Toshiro Niki Takashi Matsuba Yosuke Maeda Atsushi Takahashi Toshio Hattori Yugo Ashino 《International journal of molecular sciences》2021,22(9)
Numbers of patients with coronavirus disease 2019 (COVID-19) have increased rapidly worldwide. Plasma levels of full-length galectin-9 (FL-Gal9) and osteopontin (FL-OPN) as well as their truncated forms (Tr-Gal9, Ud-OPN, respectively), are representative inflammatory biomarkers. Here, we measured FL-Gal9, FL-OPN, Tr-Gal9, and Ud-OPN in 94 plasma samples obtained from 23 COVID-19-infected patients with mild clinical symptoms (CV), 25 COVID-19 patients associated with pneumonia (CP), and 14 patients with bacterial infection (ID). The four proteins were significantly elevated in the CP group when compared with healthy individuals. ROC analysis between the CV and CP groups showed that C-reactive protein had the highest ability to differentiate, followed by Tr-Gal9 and ferritin. Spearman’s correlation analysis showed that Tr-Gal9 and Ud-OPN but not FL-Gal9 and FL-OPN, had a significant association with laboratory markers for lung function, inflammation, coagulopathy, and kidney function in CP patients. CP patients treated with tocilizumab had reduced levels of FL-Gal9, Tr-Gal9, and Ud-OPN. It was suggested that OPN is cleaved by interleukin-6-dependent proteases. These findings suggest that the cleaved forms of OPN and galectin-9 can be used to monitor the severity of pathological inflammation and the therapeutic effects of tocilizumab in CP patients. 相似文献
77.
78.
Gaowa Bai Takashi Matsuba Toshiro Niki Toshio Hattori 《International journal of molecular sciences》2020,21(22)
Osteopontin (OPN) mediates bone remodeling and tissue debridement. The OPN protein is cleaved, but it is unclear how full-length (FL)-OPN or its cleaved form perform their biological activities in target cells. We, therefore, performed the molecular characterization of OPN in exosomes (Exo). The Exo were isolated from lipopolysaccharide (LPS)-stimulated phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages. The Exo were also isolated from PMA-differentiated THP-1 macrophages. The Exo were identified using the qNano multiple analyzer (diameter 59–315 nm) and western blotting with a CD9 antibody. LPS-stimulated cells produced more particles than non-stimulated cells. The presence of the FL or the cleaved form of OPN was confirmed using western blot analysis. A mixture of FL and cleaved OPN was also measured using an ELISA system (Ud-OPN) and their presence in the Exo was confirmed. Ud/FL ratios became low after LPS stimulation, indicating the enhanced encapsulation of FL-OPN in the Exo by LPS. These findings suggest that LPS stimulation of human macrophages facilitates the synthesis of FL-OPN, which is cleaved in cells or the Exo after release. These findings indicate that Exo is a suitable vehicle to transfer OPN to the target cells. 相似文献
79.
Modeling and identification of an electrostatic motor 总被引:4,自引:0,他引:4
The present study describes modeling and parameter identification for a high-power electrostatic motor. The motor is a synchronous motor with six phases that is modeled by a six-terminal capacitance network. A method to measure the capacitance coefficient matrix of a network using an LCR tester is proposed and demonstrated. The thrust force of the motor is shown analytically using the proposed model, which shows good agreement with empirical measurements of the motor behavior. Based on the proposed model, the effect of electrode skew is analyzed for force ripple reduction. Using the analysis, a skew motor is fabricated and tested, with the results demonstrating that a skewing electrode with a skew factor π can considerably reduce thrust force ripple. 相似文献
80.
Satoshi Watanabe Shuji Ohsaki Akiko Fukuta Tatsuya Hanafusa Kento Takada Hideki Tanaka Taisuke Maki Kazuhiro Mae Minoru T. Miyahara 《Advanced Powder Technology》2017,28(11):3104-3110
Here we quantitatively evaluated the mixing performance of a tailor-made microreactor with central-collision type through the iodide/iodate chemical test reaction, and applied the microreactor to the synthesis of zeolitic imidazolate framework-8 (ZIF-8), which is a subclass of porous coordination polymers (PCPs) or metal organic frameworks (MOFs). The chemical test reaction demonstrated excellent mixing performance of the microreactor with a characteristic mixing time shorter than 1 ms, which is approximately 100 times faster than those of a batch reactor and a millimeter-sized Y-shaped mixer. Taking advantage of the rapid and uniform mixing, the microreactor successfully produced ZIF-8 particles with high reproducibility by simply mixing aqueous solutions of zinc nitrate and 2-methylimidazole. The synthesis at room temperature resulted in ZIF-8 particles with chamfered cube shape, while a lower temperature of 5 °C produced raspberry-type spherical particles. We confirmed that prepared ZIF-8 particles have BET surface area of ~1500 m2/g and exhibit the gate adsorption behavior caused by the structural transition of the ZIF-8 framework. 相似文献