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141.
Regulation by long-chain fatty acids of the expression of cholesteryl ester transfer protein in HepG2 cells 总被引:2,自引:0,他引:2
Cholesteryl ester transfer protein (CETP) is an important determinant of lipoprotein function, especially high density lipoprotein
(HDL) metabolism, and contributes to the regulation of plasma HDL levels. Since saturated and polyunsaturated fatty acids
(FA) appear to influence the CETP activity differently, we decided to investigate the effects of FA on the expression of CETP
mRNA in HepG2 cells using an RNA blot hybridization analysis. Long-chain FA (>18 carbons) at a 0.5 mM concentration were added
to the medium and incubated with cells for 48 h at 37°C under 5% CO2. After treatment with 0.5 mM arachidonic (AA), eicosapentaenoic (EPA), and docosahexaenoic acid (DHA), the levels of CETP
mRNA were less than 50% of the control levels (AA, P=0.0005; EPA, P<0.01; DHA, P<0.0001), with a corresponding significant decrease in the CETP mass. These results suggest that FA regulate the gene expression
of CETP in HepG2 and this effect is dependent upon the degree of unsaturation of the acyl carbon chain in FA. 相似文献
142.
The OMG's Model-Driven Architecture is a strategy towards interoperability across heterogeneous middleware platforms through the reuse of platform independent designs based on the distinction of, and transformation between, platform-independent and platform-specific models.A corresponding strategy for model-driven testing requires a similar structure to facilitate, besides the generation of test cases and oracles, the execution of tests on different target platforms.In this paper, we discuss different aspects of such a strategy in a specific instance: the development of web-based distributed applications. In particular, we will be concerned with the problem of reusing platform-independent test cases and test oracles and with the generation of oracles from executable models. 相似文献
143.
Jan Hendrik Hausmann Reiko Heckel Stefan Sauer 《Electronic Notes in Theoretical Computer Science》2003,72(3):133-144
UML offers different diagram types to model behavior and dynamics of software systems. In some domains like embedded real-time systems or multimedia systems, it is necessary to include specifications of time since the correctness of these applications depends on the fulfillment of temporal requirements in addition to functional requirements. UML thus already incorporates language features to model time and temporal constraints. Such model elements must have an equivalent in the semantic domain. We have proposed Dynamic Meta Modeling (DMM) as a means for the specification of the formal operational semantics of UML models by applying graph transformation to the meta modeling of dynamic behavior. Within this paper, we extend this approach to also account for time by building on timed graph transformations. We apply these concepts to the domain of multimedia application modeling in which we adopt UML sequence diagrams. The DMM rules with time then specify an interpreter that can be used to analyze or test a model of multimedia sequence diagrams. 相似文献
144.
Gregor Engels Jochen M. Küster Reiko Heckel Marc Lohmann 《Electronic Notes in Theoretical Computer Science》2003,82(7):133-150
One of the key issues in software development, like in all engineering problems, is to ensure that the product delivered meets its specification. Verification and validation are well-established techniques for ensuring the quality of a product within the overall software development lifecycle. With models being expressed in the Unified Modeling Language, the application of verification and validation is complicated. Firstly, concerning verification, a UML model is typically not the input language of a verification tool. Secondly, with regards to validation, a UML model is also not directly executable.In this paper, we show how verification and validation can be achieved for UML models. Within our approach, graph transformation techniques are applied for automated translation of UML models into a language understood by a verification tool or directly into an implementation. By the use of such semantic-preserving transformations, both verification and validation can be lifted up to the model level, allowing for a seamless integration of verification and validation into a UML-based development process. 相似文献
145.
Marina Bouianov Oleg Bouianov Tsutomu Nagayoshi Hidetoshi Kubo Kentaro Miuchi Reiko Orito Atsushi Takada Atsushi Takeda Toru Tanimori 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2005,540(2-3):266-272
A thorough performance analysis of large-area μ-PIC detectors has been made. Through systematic simulations and comparison with test results of the two detector versions, μ-PIC1 and μ-PIC3, we have identified that low primary electron collection was responsible for the degradation of measured gas gain of the μ-PIC3 device. The test of a new detector, μ-PIC5, fabricated with a narrower inter-cathode gap and anodes raised above the insulator surface, shows a threefold increase in gas gain reaching 104 in argon 80%–ethane 20% gas mixture, which agrees with simulations. The new detector demonstrates a stable long-term operation at high gains, above 6000 measured during more than 70 h with an X-ray source, with a moderate 6% gain increase due to dielectric polarisation. 相似文献
146.
Jianliang Deng Yukika Miyashita Takeshi Sato Reiko Kuwano Junichi Koseki 《Soils and Foundations》2011,51(3):549-558
In a case history of dip slope failure caused by the 2004 Niigata-ken Chuetsu Earthquake, it has been reported that the slope contained a thin sandy soil layer. The layer may have liquefied if it had been saturated at the time of the earthquake. Undrained cyclic triaxial tests comprise one of the available experimental approaches for evaluating the liquefaction behavior of such thin sandy soil layers. In this study, a series of undrained cyclic triaxial tests was performed on specimens containing an artificial sand layer in order to investigate the effects of system compliance that are possibly induced by partial drainage caused by the changes in volume of the filter paper used to saturate the sand layer and the local drainage at the interface among the specimen, the top cap and pedestal, and the rubber membrane. The observed liquefaction behavior depended on the thickness of the sand layer under otherwise similar conditions, suggesting the significant effect of system compliance. By conducting special tests, while correcting the partial drainage, it was possible to reduce its effect on the liquefaction behavior. Cylindrical specimens with a top cap and pedestal, all having the same diameter, exhibited a smaller effect from partial drainage than prismatic specimens with an oversized top cap and pedestal. 相似文献
147.
A compression (P-) wave velocity measurement system was improved to evaluate vertical small strain Young's modulus of sand and gravel specimens. The wave was generated using a multi-layered piezoelectric actuator attached to the top cap of a triaxial cell specimen and received with two piezoelectrical accelerometers at two different positions on the specimen's side. This system includes use of a peak to peak travel time based on excitation records that were triggered by single pulse or sinusoidal wave and stacked for 128 times. The vertical Young's moduli (Ed) obtained by using this dynamic measurement were then compared with the statically measured vertical Young's moduli (Es) that were evaluated by conducting small unloading/reloading cycles on the same specimen. Two series of tests using medium and large size specimens, respectively, were conducted on three kinds of material namely Toyoura sand (D50=0.23 mm), sieved Chiba gravel (D50=3 mm) and original Chiba gravel (D50=6 mm). No significant effect of specimen size was observed on Es and Ed of Toyoura sand. Ed was found larger than Es in all three types of materials while the difference between the two was not the same. Combined effects of the dry density and the wavelength in the dynamic measurement were then discussed. 相似文献
148.
We have studied the effectiveness of surface tension on surfactants risk assessment. gamma(tox) was defined as surface tension at a point where acute aquatic toxicity of a surfactant emerges. Oryzias latipes, Daphnia magna, and Podocopida were used for acute aquatic toxicity test of 7 surfactants and 3 detergents. Gamma(tox)values were plotted on surface tension curves, and the effect of water hardness on toxicity and surface tension were examined. Results showed that gamma(tox) varies greatly by kind of surfactant or detergent. Therefore, aquatic toxicity cannot only be explained by surface tension. The change of aquatic toxicity with varying water hardness, however, could be explained by the change of surface tension. Aquatic toxicity of LAS (Linear Alkylbenzene Sulphonate) increased and aquatic toxicity of SOAP decreased with an increase of water hardness, but both gamma(tox), values were constant. Aquatic toxicity was decreased by an addition of mud soil as adsorbent into surfactant solution. The toxicity change can be explained by the surface tension since gamma(tox) value of solution with and without mud soil were equal. These results showed that the change of aquatic toxicity of a surfactant caused by water property, such as water hardness, could be explained by the change of surface tension. 相似文献
149.
Hideaki Wakamatsu Yoshihiro Sato Reiko Fujita Miwako Mori 《Advanced Synthesis \u0026amp; Catalysis》2007,349(7):1231-1246
Ring‐opening metathesis and ring‐closing metathesis (ROM‐RCM) of a cyclopentene‐yne having an ester moiety was demonstrated using first‐ and second‐generation Grubbs’ catalysts. When the reaction of cycloalkene‐yne was carried out in the presence of 5 mol % of a ruthenium carbene complex under an ethylene atmosphere at room temperature, ROM‐RCM proceeded smoothly to give a pyrrolidine derivative in good yield, which could be converted to a pyrrolizidine derivative. Furthermore, ROM‐RCM of azabicyclo[2.2.1]heptene‐ynes using the second‐generation Grubbs’ catalyst was investigated. When an azabicycloheptene derivative was exposed to a catalytic amount of a ruthenium carbene complex, pyrrolizidine and indolizidine derivatives were obtained in good yields. The distribution of these products depends on the substituents on the alkyne. When azabicyclo[2.2.1]heptene‐ynes bearing large substituents on the alkyne were treated with ruthenium catalyst 1b , a pyrrolizidine derivative was obtained as the major product. ROM‐RCM of azabicyclo[2.2.2]octene‐ynes with 1b afforded quinolizidine derivative 20 , although the yield was moderate. 相似文献
150.
An application of metal fuel cycle technology toward Self-Consistent Nuclear Energy System (SCNES) concept 总被引:1,自引:0,他引:1
Reiko Fujita Mitsuaki Yamaoka Masatoshi Kawashima Masaki Saito 《Progress in Nuclear Energy》2000,37(1-4):169-175
A fast reactor core and fuel cycle concept has been discussed for Self-Consistent Nuclear Energy System (SCNES) concept. This paper discussed loading material candidates for long-lived fission products (LLFPs) and LLFPs burning capability. Some of LLFPs were possible to be loaded in metal of the generated form. The potential for LLFP-confinement in the reactor system is discussed along with metallic fuel cycle concept. The proposed fuel cycle scheme is a successful candidate for SCNES concept. 相似文献