4,921 research outputs found

    The New Initiatives for Strengthening Public Human Resource Management

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    In this paper, we will analyze how to strengthen the public human resource management through knowledge management. Try to find out the reality of our public human resource management and the special reasons for this situation, the further to get the new methods and new measures for strengthening it

    New gapped quantum phases for S=1 spin chain with D2h symmetry

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    We study different quantum phases in integer spin systems with on-site D2h=D2xZ2 and translation symmetry. We find four distinct non-trivial phases in S=1 spin chains despite they all have the same symmetry. All the four phases have gapped bulk excitations, doubly-degenerate end states and the doubly-degenerate entanglement spectrum. These non-trivial phases are examples of symmetry protected topological (SPT) phases introduced by Gu and Wen. One of the SPT phase correspond to the Haldane phase and the other three are new. These four SPT phases can be distinguished experimentally by their different response of the end states to weak external magnetic fields. According to Chen-Gu-Wen classification, the D2h symmetric spin chain can have totally 64 SPT phases that do not break any symmetry. Here we constructed seven nontrivial phases from the seven classes of nontrivial projective representations of D2h group. Four of these are found in S=1 spin chains and studied in this paper, and the other three may be realized in S=1 spin ladders or S=2 models.Comment: 15+ pages,5 figures, 9 table

    The effects of halogen elements on the opening of an icosahedral B12 framework

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    The fully halogenated or hydrogenated B12X12 (X = H, F, Cl, Br and I) clusters are confirmed to be icosahedral. On the other hand, the bare B12 cluster is shown to have a planar structure. A previous study showed that a transformation from an icosahedron to a plane happens when 5 to 7 iodine atoms are substituted. Later, the transition was confirmed to be seven iodine substitutions based on an infrared spectroscopy study. In this study, we investigated the effects of different halogen atoms on the opening of the B12 icosahedral cage by means of density functional theory calculations. We found that the halogen elements do not have significant effects on the geometries of the clusters. The computed IR spectra show similar representative peaks for all halogen substituted clusters. Interestingly, we found a blue-shift in the IR spectra with the increase in the mass of the halogen atoms. Further, we compared the Gibbs free energies at different temperatures for different halogen atoms. The results show that the Gibbs free energy differences between open and close structures of B12X7 become larger when heavier halogen atoms are present. This interesting finding was subsequently investigated by energy decomposition analysis

    Regulation of the transcription factor NF-κB1 by microRNA-9 in human gastric adenocarcinoma

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    <p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) are a new class of naturally occurring, small, non-coding RNAs that regulate protein-coding mRNAs by causing mRNA degradation or repressing translation. The roles of miRNAs in lineage determination and proliferation, as well as the localization of several miRNA genes at sites of translocation breakpoints or deletions, have led to speculation that miRNAs could be important factors in the development or maintenance of the neoplastic state.</p> <p>Results</p> <p>We showed that miR-9 was downregulated in human gastric adenocarcinoma. Overexpression of miR-9 suppressed the growth of human gastric adenocarcinoma cell line MGC803 cell as well as xenograft tumors derived from them in SCID mice. Bioinformatics analysis indicated a putative miR-9 binding site in the 3'-untranslated region (3'UTR) of the tumor-related gene NF-κB1 mRNA. In an EGFP reporter system, overexpression of miR-9 downregulated EGFP intensity, and mutation of the miR-9 binding site abolished the effect of miR-9 on EGFP intensity. Furthermore, both the NF-κB1 mRNA and protein levels were affected by miR-9. Finally, knockdown of NF-κB1 inhibited MGC803 cell growth in a time-dependent manner, while ectopic expression of NF-κB1 could rescue MGC803 cell from growth inhibition caused by miR-9.</p> <p>Conclusion</p> <p>These findings indicate that miR-9 targets NF-κB1 and regulates gastric cancer cell growth, suggesting that miR-9 shows tumor suppressive activity in human gastric cancer pathogenesis.</p
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