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91.
We present a probabilistic and a possibilistic model for assessing the risk of a service level agreement for a computing task in a cluster/grid environment. These models can also be applied to cloud computing. Using the predictive probabilistic approach we develop a framework for resource management in grid computing, and by introducing an upper limit for the number of failures we approximate the probability that a particular computing task is successful. In the predictive possibility model we estimate the possibility distribution of the future number of node failures by a fuzzy nonparametric regression technique. Then the resource provider can use the probabilistic or the possibilistic model to get alternative risk assessments. 相似文献
92.
Christer Richt 《机械工人(冷加工)》2010,(8):41-42
现代数控机床的铣削加工可确保更高的零件表面质量,同时减少加工工序,从而可实现更高效的加工。尽管有的机床会受功率和转矩的限制,但在应用较高的主轴转速后,绝大部分工序的走刀路径规划仍然可以实现。得益于新刀具的开发和薄切屑理论的充分运用,所谓“精加工”的应用范围不断扩展。 相似文献
93.
When characterized with 13C-NMR, it was found that norbornene-ethylene copolymers had a more complicated microstructure when dimethylsilyl bis(indenyl) zirconium dichloride was used as the catalyst compared to ethylene bis(indenyl) zirconium dichloride. One could see more block sequences but less alternating sequences. For both catalysts the highest amounts of block sequences were obtained for high norbornene concentrations, medium to high Al/Zr ratios, and low polymerization temperatures. There were also more alternating sequences for high norbornene concentrations and high polymerization temperatures. The isolated norbornene units (separated by more than one ethylene unit) were all exoconfiguration. No unsaturation was seen. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1071–1076, 1997 相似文献
94.
Christer H. Bergstrm Juhana Ruotoistenmki Erkki T. Aitola Jukka V. Seppl 《应用聚合物科学杂志》2000,77(5):1108-1117
When testing copolymers of ethylene and aryl‐substituted norbornenes with the Charpy impact method it was found that under certain polymerization conditions their impact properties increased with increasing polymerization time. It was also found that this improvement on impact properties was due to increasing exo/endo ratios of the incorporated aryl‐substituted norbornene comonomers. This effect is important because impact‐resistant copolymers can be made using aryl‐substituted norbornene comonomers with low exo/endo ratios, which are more easily synthesized and purified. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1108–1117, 2000 相似文献
95.
When characterized with DMA it was found that Phenylnorbornene-ethylene copolymers with equivalent comonomer concentrations had very different storage moduli in the glassy state as well as glass transition temperatures. NMR analysis of the copolymers revealed that they had different ratios of Exo- and Endo-diastereomers even if the same comonomer composition had been used. The Exo/Endo-ratio in the polymer was surprisingly higher than in the monomer and increased with higher incorporations of the comonomer. Copolymers with higher Exo/Endo-ratios also had a tendency for lower storage moduli in the glassy state and higher tan δ peaks. These properties are valuable because more flexible and impact-resistant copolymers are obtained. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 385–393, 1998 相似文献
96.
Acute Myelogenous Leukemia Cells Secrete Factors that Stimulate Cellular LDL Uptake via Autocrine and Paracrine Mechanisms 下载免费PDF全文
Hasanuzzaman Bhuiyan Michèle Masquelier Loukas Tatidis Astrid Gruber Christer Paul Sigurd Vitols 《Lipids》2017,52(6):523-534
Leukemic cells isolated from most patients with acute myelogenous leukemia (AML) have higher low density lipoprotein (LDL) uptake than normal mononuclear blood cells. Little is known, however, about the mechanism behind the elevated LDL uptake. We investigated if AML cells secrete factors that stimulate cellular LDL uptake. Mononuclear blood cells were isolated from peripheral blood from 42 patients with AML at diagnosis. Cellular LDL uptake was determined from the degradation rate of 125I-labelled LDL. Conditioned media from AML cells stimulated the LDL degradation in the leukemic cell lines KG1 and HL60, and in isolated AML cells. The stimulatory effect correlated with the LDL degradation in the AML cells directly after isolation from blood. Conditioned media also autostimulated LDL degradation in the AML cells themselves. Concentrations of IL-6 and IL-8 in AML cell conditioned media correlated with the LDL degradation in AML cells directly after isolation from blood. Addition of R-TNF-α, but not IL-6 or IL-8, stimulated LDL degradation in HL60, KG1, and AML cells. The LDL degradation in AML cells could be inhibited by a LDL receptor blocking antibody. AML cells secrete factors that stimulate LDL uptake in a paracrine and autocrine pattern which open up therapeutic possibilities to inhibit the uptake of LDL by administration of antibodies to these factors. 相似文献
97.
The genetic basis of the differences in female pheromone blend ratio and male behavioral response in the turnip moth,Agrotis segetum, was examined by crossing individuals derived from Scandinavian and Zimbabwean populations. These two populations differ both in the ratio of the three major female pheromone components,Z5–10:OAc,Z7–12:OAc, andZ9–14: OAc and in the behavioral response of the males in both wind-tunnel and field-trapping assays. The female pheromone blend in this study is treated as the log ngZ5–10:OAc/ngZ7–12:OAc and log ngZ9–14:OAc/ngZ7–12:OAc for statistical analysis. The mean log ngZ5–10:OAc/ngZ7–12:OAc, is under control by a major autosomal factor or factors, but it is unclear what genetic factor or factors may control the mean log ngZ9–14:OAc/ngZ7–12:OAc. Frequency distributions of the proportions of each component show wide individual variation and also suggest control ofZ5–10:OAc andZ7–12:OAc by major autosomal factors, which forZ5–10:OAc may show partial dominance. Analysis of male behavioral response to synthetic blends in the wind tunnel yields inconclusive results, but suggests thatA. segetum may have a broad window of response that reflects the range of individual variation in female blends. 相似文献
98.
A Nordic Multi-Project-Chip organization with 26 design groups and 22 follow-up groups from five Nordic countries is described. The model for cooperation, the economy of the project, the applied technique and the impact on both industry and university research are dealt with. So far, 70 designs in three runs have been completed and 9 runs with 200 designs with extensive use of cell libraries are under way in 1983.Aiming towards submicron technology MPC might be the only possible way for smaller companies and universities to have circuits made. 相似文献
99.
Saccharomyces cerevisiae growing exponentially in anaerobic batch cultures that are suddenly exposed to carbon starvation will rapidly lose almost all ATP. This will cause an energy deficiency and adaptation to starvation conditions is prohibited. As a result, viability and fermentative capacity will be drastically reduced during prolonged starvation. However, if the cells are incubated in the presence of rapamycin (which will inactivate the TOR pathway) before carbon starvation ATP levels, viability and fermentative capacity will be preserved to a much larger extent compared to untreated cells. The beneficial effect of rapamycin cannot be explained by induction of a stationary phase phenotype. In fact, under these anaerobic well-controlled growth conditions, rapamycin-treated cells were still metabolically active and continued to grow, albeit not exponentially and with a reduced protein content. It is hypothesized that the loss of ATP during carbon starvation occurs because protein synthesis does not make an immediate arrest at the onset of starvation. Since there are no external or internal energy sources, this will rapidly deplete the cells of ATP. Rapamycin-treated cells, on the other hand, have already downregulated the protein-synthesizing machinery and are thus better suited to cope with a sudden carbon starvation condition. This hypothesis is strengthened by the fact that treating the cells with the protein synthesis inhibitor cycloheximide also improves the carbon starvation tolerance, although not to the same extent as rapamycin. The even better effect of rapamycin is explained by accumulation of storage carbohydrates, which is not observed for cycloheximide-treated cells. 相似文献
100.
Bill S. Hansson Gabor Szöcs Frank Schmidt Wittko Francke Christer Löfstedt Miklos Tóth 《Journal of chemical ecology》1990,16(6):1887-1897
(Z,Z,Z)-3,6,9-nonadecatriene (Z3,Z6,Z9–19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from femaleErannis defoliaria. The two components were found in a 13 ratio, with the main component,Z3,Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding toZ3,Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding toZ3,Z6,Z9–19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland ofColotois pennaria, and males ofC. pennaria andAgriopis marginaria were trapped by the mixture of the identified compounds. 相似文献