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Hypertension is common in elderly population. We designed to search comprehensively for genes that are chronologically shifted in their expressions and to define their contributions to vascular aging and hypertension. RNA sequencing was conducted to search for senescence-shifted transcripts in human umbilical vein endothelial cells (HUVECs). Small interfering RNA (siRNA), small-molecule drugs, CRISPR/Cas9 techniques, and imaging were used to determine genes' function and contributions to age-related phenotypes of the endothelial cell and blood vessel. Of 25 genes enriched in the term of "regulation of blood pressure," NPRA was changed most significantly. The decreased NPRA expression was replicated in aortas of aged mice. The knockdown of NPRA promoted HUVEC senescence and it decreased expressions of protein kinase cGMP-dependent 1 (PKG), sirtuin 1 (SIRT1), and endothelial nitric oxide synthase (eNOS). Suppression of NPRA also decreased the phosphorylation of AMP-activated protein kinase (AMPK) as well as the ratio of oxidized nicotinamide adenine dinucleotide (NAD

Vibration in pipeline system is a usual occurrence in industrial equipments. A transient fluid-structure coupling method, with data exchange between fluid and structure, is used in this paper to study the pipeline self-excited vibration under the interaction between pipe structure and internal airflow. The coupling method is based on large eddy simulation and dynamic mesh. Structured grids are used to make the displacements of grid nodes accurately calculated at each time step. The results of transient calculation show that when there is no external excitation and the given inlet mass flow rate is constant, the vibration and the pressure fluctuation of pipeline will occur, and the frequencies are close to the natural frequencies of structure and the acoustic frequencies. Furthermore, the higher the pressure inside the pipeline, the more intense the vibration and pressure fluctuation of the pipeline. By comparison of the experimental and numerical results, it is suggested that the calculation results of fluid-structure coupling are consistent with the practical situation, which indicates that the coupling method is effective and reasonable, and may be used in engineering practice.

The crystallization kinetics of nanoscale cerium dioxide particles prepared by Pechini method was investigated by various non-isothermal methods using differential scanning calorimetry. The activation energies for the crystallization calculated from modified Kissinger and Ozawa equations are 19.7 and 22.4 kJ/mol, respectively, which are much lower than that of solid-state reaction. The Avrami exponent calculated from Ozawa equation is about 1.5, indicating that the nucleation process is controlled by long-range diffusion in the early stage, and the small nuclei grow into various shapes. The nucleation rate decreases as the reaction proceeds. In addition, the kinetics of crystal growth was also studied.

An Ho3+-doped YAlO3 (Ho : YAP) single crystal has been grown by the Czochralski technique. The polarized absorption spectra, polarized fluorescence spectra and fluorescence decay curve of the crystal are measured at room temperature. The spectroscopic parameters are calculated based on Judd-Ofelt theory, and the effective phenomenological intensity parameters Omega(2,eff), Omega(4,eff) and Omega(6,eff) are obtained to be 2.89 x 10(-20), 2.92 x 10(-20) and 1.32 x 10(-20) cm(2), respectively. The room-temperature fluorescence lifetime of the Ho3+ 5I(7) -> I-5(8) transition is measured to be 8.1 ms. Values of the absorption and emission cross-sections with different polarizations are presented for the I-5(7) manifold, and the polarized gain cross-section curves are also provided and discussed.