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Context: Heart failure (HF) is one of the most serious diseases worldwide. Astragaloside IV (ASI) is widely used for the treatment of cardiovascular disease in China. Objective: To evaluate the protective effect of ASI on the HF in a Sprague–Dawley rat model of left coronary artery ligation, and investigate the angiogenesis-related mechanisms. Materials and methods: Left coronary artery was ligated to induce a rat model of HF, and the rats were treated with vehicle (saline) or different doses of ASI (0.1, 0.3 and 1 mg/kg/day) by oral gavage for 6 weeks. Cardiac function was evaluated by echocardiography. Infarct size was determined by triphenyltetrazolium chloride staining. Cardiac vascular density was analyzed by microangiography. Real-time PCR, Western blot and chromatin immunoprecipitation were performed to investigate the mechanisms. Results: ASI treatment improved the body weight and survival rate of HF rats, as well as the cardiac function of HF rats, with significantly improved ejection fraction (75.27 ± 5.75% vs. 36.26 ± 4.14%) and fractional shortening (45.39 ± 3.66% vs. 17.88 ± 1.32%). ASI reduced the infarct size of the HF rats by 47%. ASI promoted angiogenesis, with increased vascular density (2.08-fold) and induced mRNA expression of CD31 (1.81-fold) and VEGF (2.70-fold) in the ischemic heart. Furthermore, ASI induced the phosphorylation of JAK (1.89-fold) and STAT3 (2.95-fold), as well as the activity of VEGF promoter which was regulated by STAT3. Discussion and conclusions: ASI alleviated HF by promoting angiogenesis through JAK-STAT3 pathway, providing novel alternative strategies to prevent HF in the future. [ABSTRACT FROM AUTHOR]

In order to analyze the dynamic mechanical properties of viscous damper on the concrete Chinese traditional style structure with dual-lintel-column joints under seismic excitation, we designed 3 specimens for dynamic cyclic loading, including 2 specimens with viscous damper, which called controlled structure and 1 specimen without viscous damper called noncontrolled structure. The failure process and corresponding failure mode were obtained. The failure characteristics, skeleton curves, and mechanical behavior such as the load-displacement hysteretic loops, degradation of strength and rigidity, ductility and energy dissipation of the joints and the load-displacement hysteretic loops of viscous damper were analyzed. Results indicate that the hysteretic curve of viscous damper on the concrete Chinese traditional style structure with dual-lintel-column joints and viscous damper are plumper, and the structure has good ductility and capacity of energy dissipation. In the study, the concrete Chinese traditional style structure with dual-lintel-column joints and viscous damper can work together in conjunction. The load-bearing capacity of the controlled structure is significantly higher than that of the noncontrolled structure; the performance of ductility and the ability of energy dissipation are superior to those of the noncontrolled structure. All experimental results reflect that the seismic performance of the controlled structure is significantly superior to that of the noncontrolled structure. [ABSTRACT FROM AUTHOR]

An ancient palace timber structure model was made according to the requirements of fabrication methods of Song Dynasty (960-1270 A.D.). All damaged swallow-tailed mortise-tenon joints of frame were strengthened with carbon fiber reinforced polymer (CFRP) sheets. The shaking table test was carried out. The sensors were placed to measure the real-time responses of the model and the data of the shaking table itself under three earthquake waves: El Centro, Taft and Lanzhou waves. The failure mode, dynamic behavior and hysteretic energy dissipation performance were analyzed. The following conclusions are drawn; The natural period and damping ratio of the model increase along with the increasing of the input seismic energy. The range of natural periods Tis 0.53-0.67 s and the damping ratio ξ is 2.8%-4.6%. The dynamic magnification factor β decreases with the increasing of the vibration excitation. Bucket arch layer and column base dissipate seismic energy by means of frictional slippage. The joints strengthened with CFRP sheets have the strongest energy dissipation capacity and play a major role in the shock absorption. [ABSTRACT FROM AUTHOR]

Based on the data on the consumption and incomes of both urban and rural residents in China 1985--2008, the co-integration test and error correction model were introduced into the empirical analysis of the consumption of either the urban or rural residents, which deviated from their incomes for long in respect to the adjustability for the deviation. The results showed that the response rate of urban residents to the long-term deviation is slower than rural residents, though the adjustability of the former is higher than the latter. Further, the adjustability of those social strata whose incomes are different and deviating from their consumption was measured, thus finding that the potential adjustability of both the urban and rural middle-income social strata is higher than other social strata in view of long-term trend. The focal point of the income distribution as a national policy is therefore to step up the effort to develop China' s middle class, with the urban middle-income social stratum and rural middle/high-income social stratum taken in as targets. Moreover, the demonstration effect of urban residents' consumption rural residents should be in reasonable use so as to enable the consumption to play a guiding role in urban-rural integration. [ABSTRACT FROM AUTHOR]

Summary: Modern traditional‐style steel (MTS) structure is an innovative architecture structure that is widely used in China. This paper explores the possibility of using viscous damper, which can be conveniently installed between beam and column, to replace "sparrow brace" at beam–column joints to improve its seismic capability. Three 1/2.6 scaled MTS double beam–column joints, one without viscous damper and two with viscous damper, were fabricated and tested under dynamic cyclic loading. The results indicated that the primary failure modes were cracking of base metal and local bucking at the beam ends. The hysteretic curve of specimens with viscous dampers was more plump than the common specimen without viscous dampers, indicating better energy dissipation capacity. The displacement ductility ratio was about 1.79–1.96, indicating the viscous damper has little effect on the ductility, whereas in plastic stage, the energy dissipation of specimens and viscous damper increased rapidly, indicating great energy dissipating function of viscous damper. Meanwhile, the results also proved that finite element analysis may stimulate and predict the mechanical behavior of MTS double beam joints with viscous dampers. [ABSTRACT FROM AUTHOR]