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51.
Hibi Y Asai K Arafuka H Hamajima M Iwama T Kawai K 《Journal of Bioscience and Bioengineering》2011,111(5):547-549
La(3+) and not Ca(2+) increases methanol dehydrogenase (MDH) activity in Methylobacterium radiotolerans NBRC15690. La(3+)- and Ca(2+)-MDH-like proteins were found to be homodimeric (α(2)) and heterotetrameric (α(2)β(2)), respectively. N-terminal amino acid sequences of these proteins revealed that La(3+)- and Ca(2+)-MDH-like proteins were encoded by xoxF and mxaFI, respectively. 相似文献
52.
The present paper examines the accuracy of two models used to predict the capacity of single square plate anchors used in multi-anchor wall (MAW) systems constructed in Japan. Measured anchor plate capacities from full-scale in situ load tests reported in the literature are compared to predicted values using the analytical model recommended in Japan. A modified anchor capacity model is proposed that preserves the general form of the PWRC equation, but introduces correction factors to improve accuracy. The correction factors are empirically-based and are selected by back-fitting measured loads to achieve a resistance bias mean equal to one and a low coefficient of variation (COV) in bias values. The results of a large number of small-scale anchor capacity tests carried out in pullout boxes were used to guide the selection of back-fitted parameters. The correction factors account for the influence of the confining pressure (anchor depth), the plate size and the anchor rod length on the anchor plate capacity. New Nc and Nq factors are also presented as part of the new model. The bias statistics for the two models comprise an important contribution to future reliability-based calibrations of the ultimate anchor capacity limit state for MAW systems in Japan. 相似文献
53.
We examined whether nitric oxide (NO), a possible cardioprotective substance, can increase the production of interstitial adenosine in the ventricular myocardium. A flexibly mounted microdialysis technique was used to measure the concentration of interstitial adenosine and to assess the activity of ecto-5'-nucleotidase in in vivo rat hearts. The microdialysis probe was implanted in the left ventricular myocardium of anesthetized rats and perfused with Tyrode solution containing adenosine 5'-monophosphate (AMP) at a rate of 1.0 microl min-1. The concentration of adenosine in the effluent (dialysate) was measured by high-performance liquid chromatography. Dialysate adenosine obtained during perfusion with the AMP-containing solution through the probe originated from the hydrolysis of AMP by endogenous ecto-5'-nucleotidase, and the level of adenosine reflected the activity of ecto-5'-nucleotidase in the tissue. S-Nitroso-N-acetylpenicillamine (SNAP, 0.3-3 mM), an NO donor, increased the dialysate adenosine measured in the presence of AMP (100 microM) in a concentration-dependent manner. However, in the presence of an NO-oxidizing agent, 2-(4-carboxyphenyl-4,4,5, 5-tetramethylimidazoline)-1-oxyl 3-oxide (carboxy-PTIO, 1 mM), the effect of SNAP was abolished. Another NO donor, (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409, 1 mM) also increased adenosine production. 8-Bromo-cGMP (0.1-3 mM), a membrane-permeable cGMP analogue and a potent activator of cGMP-dependent protein kinase, increased the level of AMP-primed dialysate adenosine in a concentration-dependent manner. These results suggest that NO facilitates the production of interstitial adenosine in rat hearts in situ, via cGMP-mediated activation of ecto-5'-nucleotidase. 相似文献
54.
Artur Manuel Ribeiro dos Santos Caldas de Matos Reiji Suzuki Takaya Arita 《Artificial Life and Robotics》2007,11(2):175-182
Recent studies in evolutionary computation have focused on using developmental processes together with genetic algorithms
in order to achieve more complex designs. Although several models have been proposed, their growth dynamics, and their interactions
with evolutionary algorithms are still poorly understood. One particularly neglected concept in artificial developmental systems
is heterochrony: how evolution affects development by changing the timing and rate of developmental events. In this article we attempt to
address this issue by analyzing heterochronic changes in a well-known artificial developmental model, the cellular encoding
model, by using a previously developed heterochrony framework. We have conducted experiments by evolving networks to solve
a Boolean problem, and analyzed heterochronic changes in both successful and unsuccessful runs. Our findings show that owing
to its properties, the cellular encoding model strongly affects the developmental dynamics and the heterochronic changes that
occur during evolution. Our experiments also show that hypermorphic changes (a kind of heterochronic occurrence) lead to greater
evolvability in successful runs. 相似文献
55.
Hayao Imamura Takayuki Nuruyu Tatsuya Kawasaki Toshihiro Teranishi Yoshihisa Sakata 《Catalysis Letters》2004,96(3-4):185-187
For the liquid-phase partial hydrogenation of benzene at 483 K, the selectivity toward cyclohexene was greatly improved upon treating rare earth nitride with ammonia. For YbN obtained by thermal decomposition of Yb(NH2)2 at 1173 K, the selectivity of the NH3-treated YbN was 75%, in contrast to nil for the untreated YbN. 相似文献
56.
Because of the introduction of deregulation and competition in the electricity supply industry, large numbers of IPPs (Independent Power Producers) will get into the market. It has become much more important to be able to determine which generators are supplying a particular load, which generator is responsible for transmission line congestion, and what is each generator's contribution to the system losses. In this paper, we propose a way to calculate these contributions automatically. The applicability of the proposed technique is demonstrated using the EAST 10 47‐bus power system. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(3): 28–35, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10181 相似文献
57.
Isao Mochida Yoshihisa Sone Yang Duk Park Yozo Korai 《Journal of Materials Science》1985,20(9):3177-3183
The anisotropic development is studied of mesophase pitches prepared from modified ethylene tar (ETP) using AlCl3, of fractions separated by benzene, tetrahydrofuran (THF) and pyridine, and of mixed fractions, to find structural factors
affecting fusibility and optical anisotropy of mesophase pitch. Annealing was carried out at 360° C for 10 min. Each fraction
developed a unique optical anisotropy quite different from that of the parent mesophase pitch. The lightest fraction (soluble
in benzene) was highly fusible with small numbers of small anisotropic spheres. The heaviest fraction (insoluble in pyridine)
was infusible and exhibited a total mosaic anisotropy. In contrast, mixed fractions behaved like the parent mesophase pitch
in terms of liquid crystal behaviour. The extent of anisotropy and fusibility after annealing were strongly dependent on the
preparatory conditions of the parent mesophase pitch. The fusibility of mixed fractions is ascribed to the dissolving ability
of the fusible fraction and the solubility of the infusible fraction at the annealing temperature. Small molecules in the
lighter fractions also contribute to anisotropy when they are located in interlayer positions between the larger aromatic
molecules which constitute liquid crystals. Such co-operative properties of constituent molecules of the mesophase pitch can
be described in terms of a practical compatibility. 相似文献
58.
Pipelined delay-sum architecture based on bucket-brigade devices for on-chip ultrasound beamforming 总被引:1,自引:0,他引:1
Yaowu Mo Tanaka T. Arita S. Tsuchitani A. Inoue K. Suzuki Y. 《Solid-State Circuits, IEEE Journal of》2003,38(10):1754-1757
A pipelined delay-sum architecture based on bucket-brigade devices is proposed as an analog beamformer for integrated far-field steering scanning of a micromachined piezoelectric ultrasonic sensor phased array. The prototype beamformer, fabricated with an 8-/spl mu/m standard CMOS process, exhibits a total harmonic distortion of -45 dB, dynamic range of more than 65 dB, and beamforming imperfection of less than -50 dB using a 100-kHz input signal with peak voltage of 400 mV. 相似文献
59.
Yoshihisa Mano Kazuhito Ohmaki Koji Torii 《Computer Languages, Systems and Structures》1984,9(1):39-49
The authors have developed an extended intelligent terminal system MDPS with four CRT displays controlled by microprocessors and with useful programming tools in order to achieve a high-level programming environment. The system is based on the fact that reference to, comparison among, and utilization of various kinds of information are the basic but essential actions in the programming environment. Users can arrange various kinds of information spatially using simple concepts “text” and “page” of MDPS. MDPS has several advantages over conventional terminal systems. 相似文献
60.