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91.
Katsutoshi Hori Michiharu Abe Hajime Unno 《Journal of Bioscience and Bioengineering》2009,108(4):319-324
Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) produced by various bacteria has been intensively investigated as a promising biodegradable plastic, but required a supply of an expensive precursor as a secondary carbon source for its production. In a previous study, we identified a new bacterial strain, Rhodococcus aetherivorans IAR1, which synthesizes PHBV from toluene without the supply of a precursor. Toluene is the volatile organic compound most abundantly emitted to the environment. In the present paper, we show that R. aetherivorans IAR1 produces triacylglycerols (TAGs) simultaneously with PHBV. Both PHBV and TAGs were synthesized before the nitrogen source is completely exhausted. The cellular content of PHBV reached 10% of cell dry weight (CDW) and its synthesis ceased even during intermittent supply of toluene. However, accumulation of TAGs continued during cultivation and their cellular content reached 24% of CDW at the end of cultivation. Cerulenin inhibited TAG production and increased PHBV cellular content up to 30% of CDW. The mole fraction of 3-hydroxyvalerate (3HV) in PHBV produced from toluene increased from 60% to 80% during its accumulation. Fatty acid compositions of TAGs produced from acetate and toluene were different. At the end of cultivation, the mole fraction of C17:0, one of odd-carbon number fatty acids, was 5% on toluene or 10% on acetate while the mole fraction of 3HV in PHBV from toluene was as high as that in PHBV from acetate, suggesting that a C5 intermediate of toluene degradation might directly become a precursor of 3HV whereas propionyl-CoA is required for the incorporation of C17:0 into TAGs. 相似文献
92.
The author considers, mainly from the viewpoint of signal processing technologies, the current efforts for future home-use digital videotape recorders (VTRs). Recording technologies for future home-use digital VTRs are reviewed with respect to both current TV and HDTV systems. High-density recording and bit rate reduction are the major technologies needed for digital video recording with small cassettes. Recent experiments show that the technical problems, except those of equipment size and cost, have almost been solved 相似文献
93.
H Yasuda T Mine H Shibata Y Eto Y Hasegawa T Takeuchi S Asano I Kojima 《Canadian Metallurgical Quarterly》1993,92(3):1491-1496
The present study was conducted to examine the effect of activin A on growth of rat hepatocytes. EGF induced a 10-fold increase in DNA synthesis as assessed by [3H]thymidine incorporation in cultured hepatocytes. When activin A was added together with EGF, DNA synthesis induced by EGF was markedly inhibited. Inhibition was detected at a concentration of 10(-10) M, and 5 x 10(-9) M activin A almost completely blocked EGF-mediated DNA synthesis. Similarly, activin A completely blocked DNA synthesis induced by hepatocyte growth factor/scatter factor. Activin A was capable of inhibiting EGF-mediated DNA synthesis, even when added 36 h after the addition of EGF. With the same time interval, TGF-beta also blocked EGF-induced DNA synthesis. Although both activin A and TGF-beta inhibited growth of hepatocytes in a similar manner, either activin A or TGF-beta did not compete with each other in their binding when assessed by competitive binding using an iodinated ligand. When hepatocytes were incubated with EGF, release of bioactivity of activin A into culture medium was detected after 48 h or later. Activity of activin A was released from parenchymal cells but not from nonparenchymal cells. mRNA for beta A subunit of activin was detected only slightly in unstimulated hepatocytes, but markedly increased at 48 h after the addition of EGF. To determine whether endogenously produced activin A affects DNA synthesis, we examined the effect of follistatin, an activin-binding protein that blocks the action of activin A. An addition of follistatin significantly enhanced EGF-induced DNA synthesis. Finally, in partial hepatectomized rat, expression of mRNA for beta A subunit in liver was markedly increased 24 h after the partial hepatectomy. These results indicate that activin A inhibits initiation of DNA synthesis in hepatocytes by acting on its own receptor and that activin A acts as an autocrine inhibitor of DNA synthesis in rat hepatocytes. 相似文献
94.
Eto J.H. Koomey J.G. McMahon J.E. Kahn E.P. 《Power Systems, IEEE Transactions on》1988,3(4):1397-1403
A case study of residential appliance efficiency standards in the Nevada Power Company service territory is used to illustrate an integrated method for evaluating the load shape and economic impacts of demand side utility programs. The method consists of four models developed at the Lawrence Berkeley Labs: a residential energy demand model, the DOE-2 building energy analysis model, a residential hourly load and peak demand model, and a utility financial impact model. Load impacts are modeled from the bottom up with end-use energy and hourly demand models. Benefits are calculated with the aid of a production cost model and methods adapted from avoided cost offers to cogenerators and small power producers. The analysis of avoided production costs explicitly considers perturbations in future supply plans resulting from demand-side load modifications. Utility and social costs are compared to the benefits of appliance standards 相似文献
95.
A broadcast architecture network (Banet) suitable for distributed data processing is proposed. One feature of Banet is that the broadcast-within-a-group function is supported not only by the datalink level but by the transport or session-level network structure. The commitment control scheme is included in the network protocol. Design goals, physical structure and protocols are discussed. 相似文献
96.
Y Eto K Nitta K Uchida T Tsutsui K Natori A Kawashima W Yumura H Nihei 《Canadian Metallurgical Quarterly》1997,60(11):PL193-PL199
We investigated the effects of the new 5-HT2A receptor antagonist, sarpogrelate, on DNA synthesis in renal mesangial cells stimulated with 5-HT in the presence and absence of platelet-derived growth factor (PDGF)-BB. Both 5-HT and PDGF-BB demonstrated a mitogenic effect on these cells. When mesangial cells were incubated in the absence of PDGF-BB, sarpogrelate inhibited DNA synthesis in these cells in a dose-dependent manner. In the presence of PDGF-BB, sarpogrelate had a weaker anti-mitogenic effect in mesangial cells stimulated with 5-HT. Sarpogrelate was cytotoxic at concentrations over 10(-5) M according to the results of LDH release assays, and it reduced the S1 phase in mesangial cells stimulated with 5-HT by a flow cytometry. These findings suggest that sarpogrelate may be effective in the treatment of some glomerulonephritis associated with mesangial cell proliferation. 相似文献
97.
This paper proposes a boundary-element method using spatial eigenmodes for electromgnetic field analysis. Mapping the computation model with rotational symmetries, reflective symmetries or rotational symmetries including reflective symmetries to a group of spatial eigenmodes, the equivalent reduced models are obtained. In the method, the applicability becomes wide because arbitrary external source terms can be chosen. Furthermore, in a model including asymmetry regions, a new method which can save the merit of the symmetries is proposed. Finally, the validity of the proposed method is proved by numerical simulations. 相似文献
98.
Kanichi Kamiya Tokiti Noda Michio Inagaki Hajime Saito 《Journal of Materials Science》1972,7(11):1244-1248
A soft carbon and a hard carbon which were prepared from Polyvinylchloride and phenolformaldehyde resin, respectively, both by carbonizing to about 700°C, were obtained as sintered cakes by heat-treatment up to about 1800°C under the quasihydrostatic pressure of 5 kbar. Preferred orientation of crystallites relative to the compressing direction in these cakes was determined by X-ray difraction technique by using the (004) or (002) diffraction line. The soft carbon showed remarkable preferred orientation of crystallites, but the degree of orientation was dependent only a little on heat-treatment temperature (HTT). At 1200°C under 5 kbar, the hard carbon gave a sintered cake which had no appreciably preferred orientation. The degree of preferred orientation of crystallites in the cake of the hard carbon greatly increased with the increase in HTT. The difference in the dependence of preferred orientation of crystallites in the soft and hard carbons on HTT was interpreted by referring to the texture of the original carbons. 相似文献
99.
100.
This paper considers a multiobjective reliability allocation problem for a series system with time-dependent reliability. The method determines the most preferable reliability allocation and preventive maintenance schedule. The problem is multiobjective nonlinear mixed-integer. The decision making procedure is based on interactive optimization and a nonlinear programming algorithm. The method is illustrated by a numerical example. 相似文献