您选择的条件: Gao, Wei
  • Level density of odd-A nuclei at saddle point

    分类: 物理学 >> 核物理学 提交时间: 2023-07-17

    摘要: Based on the covariant density functional theory, by employing the core--quasiparticle coupling (CQC) model, the nuclear level density of odd-$A$ nuclei at the saddle point is achieved. The total level density is calculated via convolution of the intrinsic level density and the collective level density. The intrinsic level densities are obtained in the finite-temperature covariant density functional theory, which takes into account the nuclear deformation and pairing self-consistently. For saddle points on the free energy surface in the $(\beta_2, \gamma)$ plane, the entropy and the associated intrinsic level density are compared with those of the global minima. By introducing a quasiparticle to the two neighboring even--even core nuclei, whose properties are determined by the five-dimensional collective Hamiltonian model, the collective levels of the odd-$A$ nuclei are obtained via the CQC model. The total level densities of the $^{234-240}$U agree well with the available experimental data and Hilaire's result. Furthermore, the ratio of the total level densities at the saddle points to those at the global minima and the ratio of the total level densities to the intrinsic level densities are discussed separately.

  • Enhancement of hepatocyte differentiation from human embryonic stem cells by Chinese medicine Fuzhenghuayu

    分类: 生物学 >> 生物物理学 提交时间: 2016-05-05

    摘要: Chinese medicine, Fuzhenghuayu (FZHY), appears to prevent fibrosis progression and improve liver function in humans. Here we found that FZHY enhanced hepatocyte differentiation from human embryonic stem cells (hESC). After treatment with FZHY, albumin expression was consistently increased during differentiation and maturation process, and expression of metabolizing enzymes and transporter were also increased. Importantly, expression of mesenchymal cell and cholangiocyte marker was significantly reduced by treatment with FZHY, indicating that one possible mechanism of FZHY's role is to inhibit the formation of mesenchymal cells and cholangiocytes. Edu-labelled flow cytometric analysis showed that the percentage of the Edu positive cells was increased in the treated cells. These results indicate that the enhanced proliferation involved hepatocytes rather than another cell type. Our investigations further revealed that these enhancements by FZHY are mediated through activation of canonical Wnt and ERK pathways and inhibition of Notch pathway. Thus, FZHY not only promoted hepatocyte differentiation and maturation, but also enhanced hepatocyte proliferation. These results demonstrate that FZHY appears to represent an excellent therapeutic agent for the treatment of liver fibrosis, and that FZHY treatment can enhance our efforts to generate mature hepatocytes with proliferative capacity for cell-based therapeutics and for pharmacological and toxicological studies.