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41.
The nonlinear dynamic properties of highly organic soils from two levee sites in the Sacramento-San Joaquin Delta in California are described. Cyclic triaxial, resonant column and torsional shear tests were performed on thin-walled tube samples obtained from beneath levee crests, beneath adjacent berms, and in the free field such that the in situ vertical effective stresses (σvo′) ranged from about 16?to?67?kPa. These highly organic soils had considerably different organic characteristics from those used in previous studies of dynamic properties. The tested samples had organic contents of 14 to 61%, initial water contents (wo) of 88 to 496%, shear wave velocities (Vs) of 20?to?130?m/s, and organic components that ranged from highly fibrous to highly decomposed and amorphous. Secant shear modulus (G), normalized secant shear modulus (G/Gmax), and equivalent damping ratio (ξ) versus cyclic shear strain amplitude (γc) relations are presented, and their dependence on variables such as consolidation stress, organic content, prior loading history, testing device, and loading frequency are illustrated. Findings are compared to previously published results.  相似文献   
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Interleukin 12 (IL-12) has been shown to exhibit potent antitumor activity in murine tumor models through various mechanisms including the capacity to stimulate IFN-gamma production by T cells and natural killer cells. The aim of the present study was to examine the efficacy of IL-12 in inducing IFN-gamma secretion in cancer patients. A comparison was made between healthy individuals who served as controls and cancer patients for IFN-gamma production induced after the stimulation of whole blood samples with 1000 pg/ml IL-12. Samples from all healthy individuals showed positive IL-12 responsiveness. Approximately half of the samples from patients displayed levels of IFN-gamma production comparable to those observed for controls, whereas the rest of the samples exhibited almost-null responses. The incidences for reduced capacity of IFN-gamma production and null IL-12 responsiveness in cancer patients at all cancer stages or at a given advanced stage (stage IV) increased along with performance status. However, these correlated with neither the number of lymphocytes contained in the blood samples nor the tumor types. When peripheral blood mononuclear cells were isolated from patient blood samples showing null/marginal responses, and their responsiveness was examined, 7 of 13 samples exhibited positive responses. Whereas enhanced tumor necrosis factor alpha production was also observed in some patients after IL-12 stimulation, the elevation of tumor necrosis factor alpha was induced only in blood samples that showed IL-12-stimulated IFN-gamma production. These observations indicate that a remarkable difference exists in IL-12 reactivity among cancer patients, and that differential IL-12 responsiveness depends largely on performance status.  相似文献   
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We present here some results on Ir-Mo-Rh metallic catalysts for the synthesis of C2-C4 alcohols from syngas. It was found that Ir-Mo-Rh supported on silica containing small amounts of Rh exhibited much higher activity for CO hydrogenation than Ir-Mo bimetallic catalyst. The selectivity to various alcohols did not change very much upon the addition of Rh. The activity was greatly affected by the impregnation procedure of the metals in the catalyst preparation.  相似文献   
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Monitoring changes in a paddy-field area is important since rice is a staple food and paddy agriculture is a major cropping system in Asia. For monitoring changes in land surface, various applications using different satellites have been researched in the field of remote sensing. However, monitoring a paddy-field area with remote sensing is difficult owing to the temporal changes in the land surface, and the differences in the spatiotemporal characteristics in countries and regions. In this article, we used an artificial neural network to classify paddy-field areas using moderate resolution sensor data that includes spatiotemporal information. Our aim is to automatically generate a paddy-field classifier in order to create localized classifiers for each country and region.  相似文献   
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Size and asymmetry (size difference between the left and right sides) of inner ear otoliths of larval cichlid fish were determined after a long-term stay in moderate hypergravity conditions (3g; centrifuge), in the course of which the animals completed their ontogenetic development from hatch to freely swimming. Neither the normal morphogenetic development nor the timely onset and gain of performance of swimming behaviour were impaired by the experimental conditions. However, both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure compared to 1g control specimens raised in parallel. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry of lapilli was pronouncedly decreased compared with the 1g controls. These findings suggest that growth and development of bilateral asymmetry of otoliths are guided by the environmental gravity vector. Some of the hyper-g animals revealed a kinetotic behaviour on transfer to normal 1g earth conditions, which was similar to the behaviour observed in previous experiments on the transfer from 1g to microgravity (parabolic aircraft flights). The lapillar asymmetry of kinetotic samples was found to be significantly higher than that of normally behaving experimental specimens. No differences in asymmetry of sagittae were obtained between the two groups. This supports an earlier theoretical concept, according to which human static space sickness might be based on asymmetric utricular otoliths.  相似文献   
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The regulators of G protein signaling (RGS) domain of Axin, a negative regulator of the Wnt signaling pathway, made a complex with full-length adenomatous polyposis coli (APC) in COS, 293, and L cells but not with truncated APC in SW480 or DLD-1 cells. The RGS domain directly interacted with the region containing the 20-amino acid repeats but not with that containing the 15-amino acid repeats of APC, although both regions are known to bind to beta-catenin. In the region containing seven 20-amino acid repeats, the region containing the latter five repeats bound to the RGS domain of Axin. Axin and beta-catenin simultaneously interacted with APC. Furthermore, Axin stimulated the degradation of beta-catenin in COS cells. Taken together with our recent observations that Axin directly interacts with glycogen synthase kinase-3beta (GSK-3beta) and beta-catenin and that it promotes GSK-3beta-dependent phosphorylation of beta-catenin, these results suggest that Axin, APC, GSK-3beta, and beta-catenin make a tetrameric complex, resulting in the regulation of the stabilization of beta-catenin.  相似文献   
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