1,756 research outputs found

    Model Updating Based on Frequency Response Functions Using A General Finite Element Code

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    peer reviewedModel updating techniques using frequency response function (FRF) data are studied in this paper. The numerical techniques are discussed for implementation with a large commercial finite element (FE ) code. System equivalent reduction expansion process is adopted to reduce the complete FE solutions onto the experimental degrees of freedom. The rank-deficiency difficulty with this method is overcome using either of two numerical techniques: diagonal perturbation and singular value decomposition. This second technique is also used in solving the updating equation. Experimental FRF data are compared with the FE solutions, and the updated model parameters are obtained via an iteration procedure. A simplified frequency domain assurance criterion is proposed to evaluate the correlation between the FE model and the measured structure at the chosen frequencies. After verifying the efficiency of the methods with several benchmark tests, the program is applied to an aeroplane model test. Some conclusions are given and remaining problems illustrated

    The universal "heartbeat" oscillations in black hole systems accross the mass-scale

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    The hyperluminous X-ray source (HLX-1, the peak X-ray luminosity 1042erg s1\sim 10^{42}\rm erg\ s^{-1}) near the spiral galaxy ESO 243-49 is possibly the best candidate for intermediate mass black hole (IMBH), which underwent recurrent outbursts with a period of 400\sim 400 days. The physical reason for this quasi-periodic variability is still unclear. We explore the possibility of radiation-pressure instability in accretion disk by modeling the light curve of HLX-1, and find that it can roughly reproduce the duration, period and amplitude of the recurrent outbursts HLX-1 with an IMBH of ~10^5Msun. Our result provides a possible mechanism to explain the recurrent outbursts in HLX-1. We further find a universal correlation between the outburst duration and the bolometric luminosity for the BH sources with a very broad mass range (e.g., X-ray binaries, XRBs, HLX-1 and active galactic nuclei, AGNs), which is roughly consistent with the prediction of radiation-pressure instability of the accretion disk. These results imply that "heartbeat" oscillations triggered by radiation-pressure instability may appears in different-scale BH systems.Comment: ApJ in press; 15 pages, 5 Figure

    (Naphthalene-2,3-diolato-κ2 O,O′)[tris­(2-pyridyl­meth­yl)amine-κ4 N]cobalt(III) hexa­fluoridophosphate hemihydrate

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    In the title complex, [Co(C10H6O2)(C18H18N4)]PF6·0.5H2O, the CoIII ion is six-coordinated in a distorted octa­hedral geometry by four N atoms from a tris­(2-pyridyl­meth­yl)amine ligand and two O atoms from a naphthalene-2,3-diolate ligand. The asymmetric unit contains two complex cations, two hexa­fluoridophosphate anions and one uncoordinated water mol­ecule. In one of the hexa­fluoridophosphate anions, four of the F aroms are disordered over two sets of sites in a 0.632 (11):0.368 (11) ratio. In the crystal, the cations, anions and water mol­ecules are connected by O—H⋯O and O—H⋯F hydrogen bonds. π–π inter­actions are present between the pyridine rings [centroid–centroid distance = 3.814 (1) Å]

    EFFECTS OF ETHANOL EXTRACT OF RADIX SOPHORAE FLAVESCENTIS ON ACTIVITY OF COLON CANCER HT29 CELLS

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    This paper mainly studied the inhibitory effect of total ethanol extract of Radix Sophorae Flavescentis on proliferation of colon cancer HT29 cells. By reflux extraction method and with ethanol as extraction solvent, different extracts were obtained at different ethanol concentrations, different solid-liquid ratios, and at different times. And their inhibitory activities against HT29 cells were compared using MTT assay. The experimental results showed that the extraction processes under three conditions can all draw relatively high inhibition rates. The optimum ethanol extraction process conditions were as follows: a solid-liquid ratio of 1:9, 80 min of heat reflux extraction with 95% ethanol

    A STUDY ON THE INHIBITORY EFFECT OF SOLANUM LYRATUM THUNB EXTRACT ON LEWIS LUNG CARCINOMA LINES

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    The objective of this paper was to observe the effects of Solanum lyratum Thunb extract on tumour inhibition, immune function and survival time of tumour-bearing mice. Lung carcinoma-bearing mouse model was established, the tumour-bearing mice were divided into model group, CTX group, Solanum lyratum Thunb extract high-dose group and low-dose group. By the examination of tumour inhibition rate of Solanum lyratum Thunb extract in Lewis lung carcinoma-bearing mice and determination of the number of NK cells and T cell subsets, the survival rate of tumour-bearing mice was observed. Solanum lyratum Thunb extract had some anti-tumour effect in Lewis tumour-bearing mice. The tumour inhibition rate of high-dose group reached 46.28%, and the tumour inhibition rate of low-dose group was 31.42%. Solanum lyratum Thunb extract can improve the NK cell activity of Lewis tumour-bearing mice, increase the number of CD4 cells in the tumour-bearing mice, and significantly increase the survival rate of tumour-bearing mice. The study concluded that Solanum lyratum Thunb extract has some anti-tumour effect and can improve immune function and survival rate of tumour-bearing mice

    Large-scale phosphoproteome analysis in seedling leaves of Brachypodium distachyon L.

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    BACKGROUND: Protein phosphorylation is one of the most important post-translational modifications involved in the regulation of plant growth and development as well as diverse stress response. As a member of the Poaceae, Brachypodium distachyon L. is a new model plant for wheat and barley as well as several potential biofuel grasses such as switchgrass. Vegetative growth is vital for biomass accumulation of plants, but knowledge regarding the role of protein phosphorylation modification during vegetative growth, especially in biofuel plants, is far from comprehensive. RESULTS: In this study, we carried out the first large-scale phosphoproteome analysis of seedling leaves in Brachypodium accession Bd21 using TiO(2) microcolumns combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and MaxQuant software. A total of 1470 phosphorylation sites in 950 phosphoproteins were identified, and these phosphoproteins were implicated in various molecular functions and basic cellular processes by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Among the 950 phosphoproteins identified, 127 contained 3 to 8 phosphorylation sites. Conservation analysis showed that 93.4% of the 950 phosphoproteins had phosphorylation orthologs in other plant species. Motif-X analysis of the phosphorylation sites identified 13 significantly enriched phosphorylation motifs, of which 3 were novel phosphorylation motifs. Meanwhile, there were 91 phosphoproteins with both multiple phosphorylation sites and multiple phosphorylation motifs. In addition, we identified 58 phosphorylated transcription factors across 21 families and found out 6 significantly over-represented transcription factor families (C3H, Trihelix, CAMTA, TALE, MYB_related and CPP). Eighty-four protein kinases (PKs), 8 protein phosphatases (PPs) and 6 CESAs were recognized as phosphoproteins. CONCLUSIONS: Through a large-scale bioinformatics analysis of the phosphorylation data in seedling leaves, a complicated PKs- and PPs- centered network related to rapid vegetative growth was deciphered in B. distachyon. We revealed a MAPK cascade network that might play the crucial roles during the phosphorylation signal transduction in leaf growth and development. The phosphoproteins and phosphosites identified from our study expanded our knowledge of protein phosphorylation modification in plants, especially in monocots. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2164-15-375) contains supplementary material, which is available to authorized users

    Summary of 615 patients of chronic myeloid leukemia in Shanghai from 2001 to 2006

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    <p>Abstract</p> <p>Background</p> <p>To retrospectively review the incidence, treatment efficacy, we followed up newly diagnosed chronic myelogenous leukemia (CML) patients residing in Shanghai during 2001-2006.</p> <p>Methods</p> <p>All eligible cases were reviewed with the data of efficacy responses as well as overall survival (OS) and progression-free survival (PFS) time.</p> <p>Results</p> <p>A total of 615 cases entered the study. CML mainly afflicted those aged 40-60 years old and was slightly more frequent in males than females. More than 85% of the patients were in chronic phase (CP) when diagnosed. All patients were divided into four groups based on the main regimens - hydroxyurea, interferon alpha (IFN-α), imatinib, and hemopoietic stem cell transplantation (HSCT). With the median follow-up of 18 months, imatinib treatment induced 92.2% complete hematologic responses, and 64.3% complete cytogenetic responses among CML-CP patients. Overall the therapeutic efficacy in the imatinib group was higher than that in the hydroxyurea or IFN-α group. Meanwhile, in the imatinib group, all response rates of patients in CP were significantly greater than that in accelerated or blastic crisis phase. The patients treated with imatinib also showed the most promising results regarding OS and PFS. Patients receiving HSCT decreased markedly in number with the introduction of imatinib.</p> <p>Conclusions</p> <p>The number of new patients arising in Shanghai increased from 2001 to 2006. There were still patients receiving hydroxyurea and IFN-α. As the first-line regime for CML, imatinib was less administered in Shanghai before, but has received considerable development and great responses since 2003.</p
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