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Objective This research was designed to investigate the function of miR-1275 in hypoxia/reoxygenation (H/R)-induced myocardial injury and its in-depth mechanism. Methods Firstly, the differential expression of miR-1275 in patients with heart failure and healthy control were analyzed based on Gene Expression Omnibus (GEO) database. Then H/R model was constructed in vitro with AC16 cells. The qRT-PCR assay was performed to analyze the expression of miR-1275 in H/R-treated cells. Afterwards, CCK-8 assay and flow cytometry assay were carried out to detect the cells viability and apoptosis. Bioinformatics prediction, western blotting and dual-luciferase reporter assays were set to check the target gene of miR-1275. Finally, we used an Elisa to test the effect of miR-1275/HK2 axis on inflammatory factors. Results We found that miR-1275 was highly expressed in patients with heart failure and H/R treated AC16 cells than that in control group, and inhibition of miR-1275 can alleviate induced-decrease of cell viability. Subsequently, we revealed that HK2 was a downstream target gene of miR-1275, which was lowly expressed in patients with heart failure. Furthermore, our data also suggested that inhibition of miR-1275 can significantly alleviate H/R-induced myocardial injury, which can also markedly decrease the concentration of pro-inflammatory factors TNF-α, IL-1 β and increase the concentration of anti-inflammatory factors IL-10 in H/R-treated AC16 cells, while knockdown of HK2 canceled the effect caused by miR-1275 deletion. Conclusions In summing, our results illustrated that miR-1275/HK2 axis act as a potential regulator to against H/R-induced AC16 cells injury through anti-inflammatory effect.

In this current experiment, by applying the mixed-ligand synthesis method, two coordination polymers (CPs) containing Co(II) were created triumphantly with reaction between 1,3-bis(1-imidazoly)benzene (mbib) and Co(II) salts with the aid of diverse carboxylic ligands, and their chemical formulae are [Co3(opda)3(mbib)4(H2O)4]·2H2O (1, H2opda is 1,2-phenylenediacetic acid) and [Co(mpda)(mbib)]·H2O (2, H2mpda is 1,3-phenylenediacetic acid). The two compounds’ magnetic performances suggest that between the adjacent metal ions, there present the antiferromagnetic coupling. The evaluation of their treatment activity against chronic subdural hematoma was carried out and the relevant mechanism was studied simultaneously. Firstly, before the treatment of compound, the chronic subdural hematoma was generated. Furthermore, the enzyme-linked immunosorbent assay detection kit was implemented and in hematoma capsule, the anti-inflammatory cytokines level and pro-inflammatory cytokines level was detected. Additionally, the cytotoxicity of compounds 1 and 2 on the normal human cells was determined with Cell Counting Kit-8 assay. Above all, we proved compound 1 decreased the pro-inflammatory cytokines content and increased the anti-inflammatory cytokines content in the hematoma capsule, which is much stronger than that of compound 2. Both compounds 1 and 2 showed no cytotoxicity on the normal human cells.

Foundation settlement calculation has been a difficult and hot problem in geotechnical engineering study. The problems lies in the large differences between the geotechnical parameters of field and indoor test. The using of the tangent modulus method based on the field loading test to determine the calculation parameters can overcome this shortcoming, and reflect the non-linear of foundation settlement, which is a new progress of foundation settlement calculation. However, compared with other tests, the in situ plate loading test has higher difficulty, and it is also difficult to reflect the characteristics of deep soil. In this paper, by making use of systematic geotechnical test data by Riverside Campus, Texas A & M University, United States, it first examines the feasibility of the tangent modulus method used in sand foundation nonlinear settlement calculation, and then studies on the tangent modulus calculation methods of adopting lateral pressure test, The CTP test and other field tests to determine the different soil layers and lastly tests the results of loading tests for different plate sizes. The results show that the calculated parameters needed in the tangent modulus method determined by the lateral pressure test, The CTP test and other field tests are feasible. In addition, when the parameters thus determined are used in the tangent modulus method to calculate the load experimental curves of different plate sizes, the calculated nonlinear curve has good consistency with and experimental curves.

Because of the advantages such as easy construction, low cost, short construction period and mature construction techniques, soil nailing has been widely used in engineering. However, at present there is lacks of the calculation theory of soil nailing, and shortages also exist in allowable deformation values specified by current specifications: a) the safety factor of soil nailing wall is generally calculated by conventional limit equilibrium method, which has relatively low computational accuracy for complex soil distribution and can not give the relation between deformation and stability of soil nailing structure; b) current soil nailing specifications just simply specify an allowable deformation value without considering features of foundation pit, supporting types and surroundings, and these specifications also determine the early warning value for monitoring without combining the deformation with the stability of foundation pits. Thus, these shortages lead to the downward trend of usage of soil nailing that has good performance-price ratio in fact.

The soft soil in Pearl River Delta regions is characterized with high water content, high compressibility and low bearing capacity. Therefore, when building the structures on such foundation, it’s necessary to pay attention to the deformation and stability. The projects' practice shows that, when analyzing the stability on foundation pit or slope with soft interlayer, it should not only calculate the overall stability of the slope, but also calculate the stability or bearing capacity of the foundation. Although sometimes the stability of the slope meets the requirements, it doesn’t means that the bearing capacity of the foundation meets the requirements because of the existence soft interlayer, the limitations of the circle slice method and the difference between the sliding surface and the actual sliding surface.

With the further development of urban construction, engineering blasting has had a wide range of applications. However, its application environment has become more and more complex relatively. Underwater blasting, one of the applications of engineering blasting, has been increasingly used in construction of subsea tunnel and immersed tube in recent years though it has a complex influence on surroundings in operation. For the study of shock wave absorption technology of underwater blasting, this paper analyses the effectiveness of bubble curtain shielding technology used in the underwater explosion by field experiment. The test result shows that intensity of underwater shock wave approximately reduced by 80% after passing through the bubble curtain, which indicates that the bubble curtain can effectively reduce the shock wave pressure in water; vibration caused by shock wave in water approximately reduced by 20% after passing through the bubble curtain, which reflects propagation law of shock wave has changed due to the effect of the curtain.

The Rayleigh fractionation model is first deduced by the principle of dynamic reaction, which indicates that Rayleigh fractionation can be explained by dynamic characteristics of isotopic molecules in the reaction process. Subsequently, the analytic expression of evaporation line is deduced under equilibrium condition in the open systems of Rayleigh mode, which shows that it is an exponential form. The simulation results show that the slope of the evaporation line under equilibrium condition changes with the temperature that the higher the temperature is, the smaller the slope is and thus the higher the degree of enrichment is. This research can provide reference basis for better understanding the dynamic characteristics of isotopic molecules in evaporation process.

A test of bending resistance and reinforcement is carried out on RC beams reinforced by applying sheet of glass fiber reinforced plastics (GFRP). A study and analysis is given to the traits of bending and rupture of RC beams reinforced by applying GFRP and to the effect of GFRP on ultimate bearing capacity and stiffness of the beams. The strengthening effect is investigated to give guidance in practice work.

Due to the characteristics of the physical mechanical properties of soft ground, reasonable foundation treatments are usually necessary before it meets the need of foundation deformation and load requirements. How to choose a reasonable foundation treatment method which has obvious virtues of economical expenditure and shorter construction period is an urgent problem emerging in engineering construction in the Pearl River Delta. While drainage sand well is used widely in soft soil foundation treatment in the Pearl River Delta. In this paper, a simplified calculation method is proposed to calculate the strength of soft soil foundation treated by sand well after drainage consolidation.

EPS (Expanded Polystyrene) materials have the features of super light, water resistance, anti-ageing, corrosion resistance and well supporting itself .They are now widely used in civil engineering because of their unique features for its unique characteristics. This paper introduces the properties of EPS and the application of EPS in the road and bridge engineering. The correlation analysis showed that The pressure on the foundation can be greatly reduced by the EPS filling embankment in soft foundation, and the settlement and displacement of the EPS embankment are small and its stability is good. The application of EPS in the embankment of a bridge can solve the bumping problems due to differential settlements of road and bridge. EPSs application can reduce differential settlement in the embankment splicing and strengthen intensity in the embankment splicing, which making the new and old expressway as a union in the road-widening project.

Based on the analysis of geological data and meteorological data of landslide, the mechanism of rainfall-induced landslides was analyzed, and the relationship between landslide and rainfall was further discussed, including the landslides and rainfall distribution, the relationship between landslide and frequency of rainstorm, and the time relationship between landslide and rainfall. The results show that the probability of landslide occurrence and the quantity of landslides have positive correlation with rainfall. The landslides mainly occur from May to September in which the monthly mean rainfall is large. Meanwhile, landslide occurrence is closely related to the characteristics of rainfall of that day and rainfall of early days. When the daily rainfall exceeds 50mm or 10 days accumulative rainfall exceeds 100mm, the landslide is prone to occur and the occurrence rate of the latter is higher.

Hybrid knowledge representation schemes, including production rules, object-oriented programming, and procedural methods, are employed to express expert heuristics and standard emergency knowledge during the development of the knowledge-based system (KBS) for emergency decision for disaster reduction. This approach renders it possible to take advantages of the characteristics of each method. The system can provide the user with advice on Preliminary plan evaluation, Plan optimization, Plan evaluation ,Plan summary and Miscellaneous.

Based on the one-dimensional constitutive relationship of unsaturated soils, this thesis has established the calculation model for embankment settlement with lateral deformation and without lateral deformation in accordance with the mechanic characteristics and in consideration of the influence of water environment. In addition, the thesis has provided the calculation methods for embankment settlement under various working situations (like under the situations of external load function, self-weight effect, increasing of the groundwater level, the invasion effect of rain water and the comprehensive effect of various working conditions) and used the settlement deformation results from the experiments of embankment models to check the calculation method. The method put forward in this thesis could not only be used in the calculation of the settlement deformation under load, but also could be used for the calculation of the deformation caused by the changes of water content in the embankment.

The aqueous environment quality plays an important role in controlling the circulation track of ecological environment. Environmental isotopes widely exist in various kinds of water and can be extensively applied in water environment. Isotopes as natural tracers can be used to trace the transportation process of water in hydrologic cycle and the variations of isotopic value can also provide the information about the transference of contamination. The dynamical process of the movement and mix of waters can be studied by applying the composition characteristics of stable isotopes contained in natural waters, thus the main processes of water resources formation and aqueous environment evolution as well as their driving forces mechanism can be revealed. In this paper, the development history of the application of stable isotopes in the water circulation is reviewed, the application theory and analytical method of the environmental stable isotopes, and the new progress of the applied study on water resources formation and aqueous environment evolution are mainly discussed.

Problems and flaws of existing safety criteria for vibration are reviewed. A simple consideration of particle vibration velocity cannot fully reflect the inherent law of effects of explosion earthquake on structures. Sometimes the occurrence of explosions exceeding the standard velocity for safety will not necessarily cause damage to structures and those below the standard velocity for safety may destroy structures. For this reason, the free vibration frequency of structures and the safety margin of the structure should be considered. Based on safe, practical and convenient conditions, that in respect of safety criteria for dike and slope exposed to vibration, two indicators, i.e., stability factor of dike and slope and vibration velocity of particle, can be used to determine the effect of vibration on them is proposed. That is to say, pseudo-static method is adopted to make vibration inertia force equivalent to a static force on slope bars and then strength reduction method or limit equilibrium method is used to calculate the safety factor, which can directly evaluate the stability of slope. In combination with the particle vibration velocity given in specifications, the safety of dike and slope can be determined. Lastly, specific engineering cases are used to validate the rationality of this criterion. This method can serve as a reference for similar projects

When strength reduction method is used for side slope analysis, only the intensive parameters are reduced and deformation parameters are not. The ideal elastoplastic model is adopted, and the safety factor is basically in agreement with that of the traditional limit equilibrium method. Main result is the safety factor of side slope, but non-linearity of soil is not considered actually during calculation, so it's hard to arrive at a real deformation field. Based on the deformation modulus elastoplasticity strength reduction method, research of this paper can achieve a more truthful deformation field. Considering the deficiencies in the current slip surface search techniques, this paper mainly studies how to determine the slip surface directly through the slope deformation field and stress field based on the analysis to their characteristics and the formation mechanism and characteristics of slip surface. Three methods to determine the slip surface are worked out: One is to use displacement gradient to identify the most disadvantageous slip surface; The second one is to determine the slip surface using the characteristics of FLAC calculation method and the characteristic that nodal velocity at non-slip area is near to zero and nodal velocity at slip area is very great; The last one is to use the deviation survey method in slope monitoring to track the nodal displacement in numerical analysis, and take the points with displacement catastrophe as those on the slip surface, and link those points to form a curve and finally get the critical slip surface. Analysis is made to the slip surface of clay slope with weak layer. Position of slip surface determined through these three methods is basically the same. Compared with traditional critical equilibrium method, these three methods can not only be applied to homogeneous side slope, but also be used to determine the slip surface of heterogeneous side slope. This paper makes a research on expansion of the application field of deformation modulus elastoplasticity strength reduction method.

In-situ experimental results on the elastic wave velocity of Earth materials at high pressure and high temperature in combination with data from seismic observation can help to inverse the chemical composition, state and migration of materials in Earth's interior, providing an important approach to explore information of deep earth. Applying the Brillouin scattering into the Diamond Anvil Cell (DAC) to obtain the in situ elastic wave velocities of minerals, is the important approach to investigate elastic properties of Earth's Interior. With the development of DAC technology, on the one hand, the high temperature and high pressure experimental environment to simulate different layers of the earth can be achieved; on the other hand, the optical properties of DAC made many kinds of optical analysis and test methods have been widely applied in this research field. In order to gain the elastic wave velocity under high temperature and high pressure, the accurate experimental pressure and heating temperature of the sample in the cavity should be measured and calibrated first, then the scattering signal needs to dealt with, using the Brillouin frequency shift to calculate the velocity in the sample. Combined with the lattice constants obtained from X ray technique, by a solid elastic theory, all the elastic parameters of minerals can be solved. In this paper, firstly, application of methods based on optical spectrum such as Brillouin and Raman scattering in elasticity study on materials in Earth's interior, and the basic principle and research progress of them in the velocity measurement, pressure and temperature calibration are described in detail. Secondly, principle and scope of application of two common methods of spectral pressure calibration (fluorescence and Raman spectral pressure standard) are analyzed, in addition with introduce of the application of two conventional means of temperature calibration (blackbody radiation and Raman temperature scale) in temperature determination. Lastly, geophysical applications of mineral elasticity are discussed on the basis of the recent research results derive from Brillouin scattering system of wave velocities for major minerals in Earth's lower mantle (perovskite, ferropericlase, etc.), and the future research work is inspected.

Tracer-based hydrograph separation relying on the mass balance equations of water and isotopic compositions is very appealing and widely used in basin hydrology, due to its simplicity. However, much uncertainty of this method is presented in practical applications, which is mainly affected by model assumptions. In this paper, theoretical analysis is conducted to test the reality of some fundamental assumptions involved in isotopic hydrograph separation method. The results indicate that soil water plays an important role in stormflow generation, and the previous assumption that contributions from soil water are negligible in hydrograph separation seems to be unrealistic. It shows that the bigger the contribution rate of soil water is, or the greater the difference of the isotopic compositions of soil water and base flow is, and thus the bigger the estimated error of the proportion of pre-event water is. Finally, some feasible suggestions are put forward to improve the application of the isotopic hydrograph separation method.

To investigate the prevalence and risk factors of diabetic retinopathy (DR) among type 2 diabetic patients aged over 30 in Shanghai central area.1039 patients diagnosed with type 2 diabetes mellitus (DM) aged over 30 were investigated by randomized cluster sampling in Shanghai central area and data from 767 of those patients were analyzed.(1) Among all of the 1534 digital ocular fundus images from 767 patients, 87.6% of the images from 672 patients were gradable. (2) Among all of the 672 patients with gradable ocular fundus images, the prevalence of non-proliferative diabetic retinopathy (NPDR) was 21.6%, while proliferative diabetic retinopathy (PDR) was 1.3%. The rates of mild, moderate and severe NPDR were 8.8%, 11.2% and 1.6% respectively. (3) DR patients were characterized with elder age, higher HbA1c, urea nitrogen and serum creatinine. DM duration and the level of fasting plasma glucose were risk factors for DR.The overall prevalence of DR in type 2 diabetic patients aged over 30 in Shanghai central area was 22.9% and the DR risk factors were found to include duration of diabetes and fasting plasma glucose level.

To explore the effects of berberine and insulin on adiponectin mRNA expression in 3T3-L1 adipocyte.The 3T3-L1 adipocyte was treated with berberine and insulin for 48 hours, the level of adiponectin mRNA in 3T3-L1 adipocyte expression was determined with semiquantity RT-PCR using beta-actin as internal reference.The level of adiponetin mRNA in 3T3-L1 adipocyte was increased after treated with berberine only (P0.05), the effect of berberine was inhibited by high concentration insulin (P0.05).In vitro, berberine increases the expression of adiponectin in 3T3-L1 adipocyte, insulin inhibits the effect of berberine.