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The geometric nonlinearity caused by gravity can not be neglected when conducting ground modal test of solar array on the ground. So a new model updating method for flexible structures considering the influence of gravity is proposed in this paper. First, the stress stiffness matrix in ground environment is derived, then the modes are calculated by solving the generalized eigenvalue problem. After matching tested mode shapes with calculated ones, the sensitivity analysis of the parameters is carried out. Then the proper parameters are chosen and updated by using a iteration process. A numerical simulation of a deployed and locked solar array is conducted, it is found that gravity has influence on the modal frequency. The elastic parameters of the single panel and the connection stiffness of the hinges between different solar array panels are updated step by step. The study shows that proposed method is fast and accurate. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of geochronology, in situ clinopyroxene mineralogy, geochemistry and isotope geology for the Triassic mafic magmatism of the central Tibetan Plateau. Moreover, the results are used to understand the development of a continental back-arc basin and the generation of back-arc basin magmatism. Zircon U-Pb isotope analyses indicate that these rocks were formed during the Middle Triassic (c. 231 Ma). Both the mafic rocks and the trapped melt calculated by the clinopyroxene/melt partition coefficient (Dcpx/melt) exhibit distinct enrichments in light rare earth elements (LREE) and Th with pronounced depletions in Nb and Ta, which are similar to the geochemical composition of typical continental back-arc basin basalts. Geochemical features and isotopic variations indicate that the mafic melts originated from a depleted mantle modified by c. 10% crustal components. The ratios of Zn/Fet and REE further suggest a spinel-bearing peridotite source. Considering other regional geological data, we argue that the origin of Triassic mafic magmatism should be attributed to the extension of a continental back-arc basin. Slab rollback and mantle plume activity played vital roles in the formation and development of a continental back-arc basin in the central part of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Based on Finite element method-Direct boundary element method (FEM-DBEM) and Finite element method-Indirect boundary element method (FEM-IBEM) approach, the bearing cylinder-skin structural-acoustic coupling models considering onlyinternalorexternalacoustic field and both inside and outside acoustic field are established. The structural-acoustic coupling analysis under random base excitation is researched. Further, the coupled effect of internal/external acoustic field and structural-acoustic coupling on the inherent characteristics and dynamic response is analyzed with the emphasis on. Results show that coupled effect results in the decrease of its nature frequencies, but has no effect on the modal shape. Single acoustic field effect results in the increase of the nature frequencies more than both inside and outside acoustic field effect. The coupled effect also results in the overall decrease of dynamic response, but causes increase of the dynamic responsein the places where is parallel to the direction of excitation. In addition, influence of internal acoustic field on the dynamic responseis greater than the external acoustic field. [ABSTRACT FROM AUTHOR]

The decoction of a combination of two Chinese herbs, Astragali Radix (the roots of Astragalus membranaceus var. mongholicus) and Angelicae Sinensis Radix (the roots of Angelica sinensis), here named as A & A, has been demonstrated to have renoprotective effects in several animal models and may be considered as a complementary therapeutic medicine for chronic kidney disease. In this study, genomic approaches were employed to identify expression signatures in the obstructed kidney, which may be linked to the molecular actions associated with anti-fibrotic effects of A & A. Ninety-six male Wistar rats were divided randomly into sham, SAA (sham + A & A), UUO (unilateral ureteral obstruction), and UAA (UUO + A & A) groups. The rats in the SAA and UAA groups were administered A & A (14 g/kg) by oral gavage once daily; the ones in the sham and UUO groups were given equal volumes of water. Eight rats from each group were sacrificed at days 3, 7, and 10 after the operation, respectively. Changes in gene expression in the kidneys were determined using Affymetrix RAE-230A GeneChips. The differential expression of known genes between UAA and UUO was confirmed by RT‐PCR. The results revealed that 40, 65, and 104 genes were upregulated and 30, 36, and 40 genes downregulated in UUO compared with the sham group at days 3, 7, and 10, respectively. Compared to the UUO group, eight genes were upregulated and two genes were downregulated at day 3 in the UAA group, and two genes were upregulated at day 10. These genes included transient receptor protein 3 (TRP3), bone marrow stromal cell antigen 1 (BST-1), peroxisomal biogenesis factor 6 (PEX6), xanthine dehydrogenase (XDH), cytochrome P450 subfamily I member A1 (CYP1A1), serine/cysteine proteinase inhibitor clade E member1 (PAI-1), fibroblast growth factor 23 (FGF23), and five ESTs. Among these genes, differential expression of PAI-1, FGF23, and CYP1A1 were further confirmed by RT‐PCR. These data provide the evidence that the anti-fibrotic effects of A & A are mediated through multiple pathways in obstructive nephropathy, and novel mechanisms may be involved in the increasing degeneration of ECM, decreasing ROS reaction, and regulation of the calcium-phosphate metabolism. [ABSTRACT FROM AUTHOR]