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The stability of the arch dam shoulder is an important element in the analysis of the safety and stability of arch dams. The classical calculation method of arch dam shoulder slip resistance needs to assume the bottom sliding surface of the dam shoulder slider and ignore the influence of the fault and fracture joint group in the rock body of the dam shoulder on its shoulder slip resistance stability. In order to take into account the influence of faults and fracture joint groups to the rock mass, this paper used genetic algorithm to search for the critical sliding surface of the dam shoulder anti-slip based on the time course analysis method and analyzed the change of vibration intensity anywhere on the critical sliding surface of the dam shoulder slider. The slip resistance of the concrete arch dam shoulder was investigated in terms of sensitivity to shear strength parameters and ground vibration. The study result shows that the friction coefficient of the structural surface has less influence to the slip resistance stability of the dam shoulder, while the slip resistance stability performance of the dam shoulder is most sensitive to the cohesive force on the rock bridge, and the influence of cohesive force to the slip resistance stability performance is stronger than that of the friction coefficient, and the influence of ground vibration to the slip resistance stability performance of the arch dam shoulder is weaker. [ABSTRACT FROM AUTHOR]

The early spread of Chinese tea in Europe was mainly carried out through tea activities in the exploration of the East by multiple subjects such as navigators, missionaries, businessmen, doctors, botanists and nobles. In general, it showed the historical route of smelling, drinking and recognizing tea, of which people’s impression of tea mainly originated from the literature transmission of various travel notes and the imagination of oral transmission. There was once a cognitive bias and misreading of the sanctification and stigmatization of tea, and tea became the symbolic intention for the imagination of the East and collective memory. With the introduction of tea products into Europe, the elite class played a leading role in forming the fashion of tea consumption and the public demand for tea based on physical concerns was growing. As foreign countries have deepened their cognitive needs of Chinese tea, the misreading of tea as a type of foreign culture has gradually been clarified, and has been localized in tea botany, medicine, chemistry and other aspects. [ABSTRACT FROM AUTHOR]

0bjective To study the inhibition effect of Osterix specific small interfering RNA(siRNA)on Osterix gene expression in bone marrow mesenchymal stem cells，and to screen the most efficient Osterix specific siRNA．Methods According to the principle of siRNA design，Osterix specific siRNA(1-3)was designed and the bone marrow mesenchymal stem cells were transfected．The expression of Osterix gene was detected using real-time quantitative PCR and Western blotting．Results Endogenous Osterix expression was efficiently blocked in bone marrow mesenchymal stem cells by Osterix siRNA··2 in a dose··and time-dependent manner．Osterix expression decreased significantly along with the increase of siRNA一2 dose within 50-200 nmol／L and it was the lowest at 48h after transfection with 200nmol／L of siRNA一2(P<0．05)．Conclusion The expression of Osterix in bone marrow mesenchymal stem cells can be blocked efficiently in a dose and time dependent manner by specific siRNA． [ABSTRACT FROM AUTHOR]

The aim of the experiment was to study the amount of oil-producing Rhodotorula strain PR61 as fish feed additive and the effect of wall breaking treatment on feeding effect. A total of 375 red crucian carp seedlings with an average body weight of 4~5 g were randomly divided into five groups with three replicates per group and 25 fish per replicate. Fish in blank control group were fed with 100% basic feed, fish in positive control group were fed with 100% basic feed + 0.25% betaine hydrochloride, fish in T1 group were fed with 99.5% basic feed + 0.5% unbroken red yeast, fish in T2 group were fed with 99.5% basic feed + 0.5% broken red yeast, and fish in T3 group were fed with 99% basic feed + 1.0% broken red yeast. The experiment lasted for 28 d. The results showed that the PR61 strain was rich in nutrition, with protein content up to 45.2%, oil content up to 38.93%, the PR61 strain also contained carotenoid, aspartate, serine and totally 17 kinds of amino acids, and the total amino acid was 44.32%. The survival rate of red crucian carp in T2 group and T3 group was 100%, which was significantly higher than that of blank control group and positive control group (P<0.05). The body weight growth rate of red crucian carp in T3 group was significantly higher than that in other groups (P<0.05), the body length growth rate was significantly higher than that in blank control, positive control group and T1 group (P<0.05), and the feed coefficient was significantly lower than that in other groups (P<0.05). The a* value and L* value of the back skin of red crucian carp in T3 group were significantly higher than those in other experimental groups (P<0.05). The activity of SOD and GSH-Px in serum of red crucian carp in T2 group and T3 group were significantly higher than those in other groups (P<0.05), and the content of MDA was significantly lower than that in other groups (P<0.05). The CAT activity of red crucian carp in T3 group was significantly higher than that in blank control, positive control group and T1 group (P<0.05). The study indicates that adding PR61 in feed can significantly improve the survival rate, weight growth rate and antioxidant enzyme activity of fish fry, decrease the feed coefficient. The growth index of the fish fry reaches the best level and the color of fish body is more vivid when the supplemental amount of red yeast is 1.0%. [ABSTRACT FROM AUTHOR]