Transient response of bridge piers under eccentric impact of near-fault earthquake.

To study the influence of near-fault earthquake on pier failure, establish a double-span continuous girder bridge. The seismic response of the bridge is calculated using the transient wave function expansion method and the indirect mode function superposition method. Solve the dynamic and displacement responses, and the effect of the vertical separation of the bridge on the eccentric compression of the pier is analyzed. The results show that under the near-fault vertical seismic action, the separation can significantly change the horizontal deformation at the top of the pier, and neglecting the separation may underestimate the eccentric compression of the pier. Calculations for different pier heights and girder spans show that separation has a greater effect on the longitudinal deformation of the pier top. Therefore, the reasonable design of longitudinal limit device on pier top in the near-fault area is helpful to reduce the damage of eccentric bridge impact.

Protective effects of naringenin in cardiorenal syndrome.

BACKGROUND: Cardiorenal syndrome is a complicated and bidirectional interrelationship between the heart and kidneys. Naringenin (NG) is a naturally occurring flavonoid possessing various biological and pharmacological properties. MATERIALS AND METHODS: We tested whether NG could improve cardiac and renal function in a rat model of cardiorenal syndrome. RESULTS: The results showed that NG-attenuated cardiac remodeling and cardiac dysfunction in rats with cardiorenal syndrome, as evidenced by decrease of left ventricle weight (LVW), increase of body weight (BW), decrease of LVW/BW, decrease of concentrations of serum creatinine, blood urea nitrogen, type-B natriuretic peptide, aldosterone, angiotensin (Ang) II, C-reactive protein, and urine protein, increase of left ventricular systolic pressure and falling rates of left ventricular pressure (dp/dtmax), and decrease of left ventricular diastolic pressure, left ventricular end-diastolic pressure, and -dp/dtmax. NG significantly inhibited the increase of lipid profiles including low-density lipoprotein, TC, and TG in rats. In addition, NG significantly inhibited the increase of cardiac expression of IL-1ß, IL-6, and interferon γ. Moreover, NG decreased malonaldehyde level, increased superoxide dismutase activity and glutathione content in rats, and increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and catalytic subunit of γ-glutamylcysteine ligase (GCLc) in rats and Ang II-treated cardiac fibroblasts. Inhibition of Nrf2 and glutathione synthesis significantly suppressed NG-induced decrease of ROS level. Inhibition of Nrf2 markedly suppressed NG-induced increase of GCLc expression in Ang II-treated cardiac fibroblasts. CONCLUSIONS: The data provide novel options for therapy of patients and new insights into the cardioprotective effects of NG in cardiorenal syndrome.