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We have repeatedly demonstrated that electroacupuncture (EA) of "Neiguan"(PC 6) can improve myocardial ischemia in rats. The present study was designed to investigate the metabolomic profile of peripheral blood se-rum and myocardium involving EA-induced improvement of myocardial ischemia-reperfusion injury (MIRI) in rats by using nuclear magnetic resonance spectroscopy.Thirty male SD rats were equally randomized into blank control, model and EA groups. Rats of the control group were only banded for 20 min, once a day for 7 days. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min, and rats of the model group were banded as those in the control group. EA (10 Hz/50 Hz, 1 mA) was applied to bilateral PC 6 for 20 min, once daily for 7 days. The blood samples and left ventricular myocardial tissues were collected for assaying the profiles of differential metabolites usingA total of 19 differential metabolites (17 down-regulated, 2 up-regulated) in the serum and 14 differential metabolites (13 down-regulated and 1 up-regulated) in the ischemic left myocardium were identified after MIRI. Of the 19 serum differential metabolites, amino acids (leucine, isoleucine, valine,alanine, lysine, glycine, glutamine), 3-hydroxy butyric acid (3-HB), lactic acid, acetate, N-acetyl glycoprotein (NAc), acetone, acetoacetate, succinate, polyunsaturated fatty acids (PUFA), creatine, glycerophosphocholine (GPC) were down-regulated; while low density lipoprotein (LDL), LDL/very low density lipoprotein(LDL/VLDL)and glucose obviously up-regulated. Of the 14 myocardial differential metabolites, amino acids (alanine, lysine, glutamate, glutamine, aspartate, taurine, glycine, threonine), GPC, creatine, lactic acid, adenosine monophosphate (AMP), nicotinamide adenine dinucleotide (NAD＋) were significantly decreased, and glucose was up-regulated. Following EA treatment, most of the decreased serum differential metabolites except acetone, acetoacetate and PUFA, and the increased serum LDL, LDL/VLDL and glucose recovered, basically close to the control level; and the decreased myocardial creatine, GPC and NAD＋ were also apparently up-regulated and the increased myocardial glucose was down-regulated. But, myocardial threonine and AMP still presented a decreasing state. Although the pattern of myocardial differential metabolites of the EA group had a trend to be close to the control group, the significant difference still existed, while the metabolic pattern of serum metabolites in the EA group was close to that of the control group.EA stimulation of PC 6 can regulate serum or/and myocardial metabolites as amino acids, carbohydrates, lipids, etc. in MIRI rats, of which both serum and myocardial creatine, GPC and glucose may be jointly confer a favorable potential for EA-induced improvement of MIRI.

The influence of initial composition and the united solid back diffusion (SBD) effects on the calculated solidification paths (SP) of a series Al–Fe–Si ternary eutectic alloy were analyzed. The calculation programme was coupled with Thermo-Calc to calculate equilibrium for phase diagram information. The calculated results showed that initial compositions and SBD coefficient had important effects on SP of the Al–Fe–Si ternary eutectic alloys. The SP of the five Al–Fe–Si ternary alloys were divided into three categories: \( L \to (L + \beta ) \to (L + \alpha + \beta ) \to (L + \alpha + \beta + \text{Si}) \), \( L \to (L + \alpha ) \to (L + \alpha + \beta ) \to (L + \alpha + \beta + \text{Si}) \), and \( L \to (L + \alpha ) \to (L + \alpha + \text{Si}) \to (L + \alpha + \beta + \text{Si}) \). It was found that the volume fraction of eutectic phase decreases obviously with the increase of the SBD coefficient. Solute distribution coefficients of KFe and KSi in Al–0.08Fe–4.8Si alloy were also calculated and analyzed.

The high solid loading slurries with ZnO-Al2O3powders stabilized with polyelectrolytes have been studied. The influence of Sodium poly(acrylate) (PA 30) on the fluidity and stablility of the slurries was investigated. Morphological features of ZnO-Al2O3powders in suspension and fracture surface of green compact were observed using TEM and SEM. The slurries with pH 9 were prepared after milled using ZnO mixed powders and the PA 30 solution of pH 8. As 0.2 wt% PA 30 added, the lowest viscosity and the highest sediment were obtained. ZnO and Al2O3particles had been homogeneous dispersed. The maximum density (66.7 %TD) of green compact was obtained.

Q43Y-85D type crocodile hydraulic clipping machine was taken as research object to optimization design. A finite element model for clipping machine was built using shell unit as fundamental unit. ANSYS12.0 finite element method was used to analyze the deformation and stress distribution of the shear platform model of hydraulic clipping machine. The result showed that the maximum equivalent stress at the dangerous area was 368.162 MPa and the maximum elastic strain was 0.1814×10-2 mm. After the structural optimization design, it was found that the maximum equivalent stress decreased to 186.238 MPa which did not exceed the material’s yield limitation 215 MPa and the maximum elastic strain decreased to 0.919×10-3 mm which satisfied the requirement of stiffness.

With the development of transportation, subway is more and more important to every city, but the security of underground railway track faces with serious challenges. Tunnel excavation cross-section types have rectangle, roundness, arch, composite one and so on. In the tunnel excavation under Feng-tian Road in Chongqing, we chose three cross-section types for obtaining optimal scheme by finite element method (FEM). The efficiency and reliability of the optimized tunnel excavation cross-section were demonstrated by simulation results by FEM software Abaqus, and the tunnel excavation engineering under Feng-tian Road in Chongqing. Hope that this work can provide a reference to other tunnel excavation engineering.

Oxide-dispersion-strengthened (ODS) ferritic alloys are fascinating materials for future fusion power reactors due to these materials would allow a substantial increase of the operating temperature. Y-Ti bioxides strengthened Fe-Cr alloy was produced by mechanical milling (MM) followed by hot pressing (HP). Microstructure changes of the mixed powders during mechanical milling and subsequent hot pressing were structurally characterized by means of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The observations of structure of the mixed powders after MM indicated that the powders are fractured and welded with rotation and vibration of container during mechanical milling. And the particle size decreases with increasing milling time. Nanoscale Y-Ti bioxides were formed during the HP process.

Transparent conducting aluminum-doped zinc oxide (AZO) films with different film thickness had been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall-effect measurement and optical transmission spectroscopy, which were strongly influenced by film thickness. With the film thickness increasing from 140 nm to 710 nm, the resistivity decreases from 9.78 × 103 to 3.23 × 103 Ω.cm and an average optical transmission decreases from 88% to 80% in the visible range and the optical bandgap decreases from 3.47 to 3.24 eV.

The thermal effect arisen from absorbing inclusions is the main factor which causes the damage of optical materials or component irradiated by the longer pulse duration laser. The unsteady heat conduction depends markedly on both the thermal properties of inclusions and the parameters of laser. Based on the differential equation of heat conduction, the temperature distribution caused by single absorbing inclusion is solved by use of finite difference method. The effect of the laser intensity and the pulse duration on temperature field is analyzed in detail. The result demonstrates that the smaller size inclusion and the smaller pulse duration cause relative safe thermal effect, consequently, the less probability to be damaged by thermal effect.

The thermal effect caused by absorbing inclusions irradiated by multi-pulse laser is different from that of single pulse laser. The temperature field induced by multi-pulse laser depends markedly on both inclusion size and pulse duration, and repetition interval of pulse. Based on the differential equation of heat conduction, the temperature field caused by single absorbing inclusion is solved by use of finite difference method. The effect of inclusion size, pulse duration and repetition interval of pulse on the evolution of temperature field at the center of inclusion and interface between inclusion and dielectric are discussed qualitatively.

The curriculum construction is a very important work leading to the excellent course. Welded Structure (including 40 class hours) is one of main and compulsory course for the major of Material Molding and Control Engineering in our university. It is very important and necessary to construct the course in time. Based on the project of High Quality Curriculum Construction for Welded Structure undertaken by the authors, this paper makes a discussion on the original ideas, goals and contents, strategies and measures of the project. Meanwhile, the course construction and reform of Welded Structure are introduced from following aspects, such as curriculum setting, teaching contents and methods, teaching staffs, teaching quality management and supervision, online teaching resource construction. The purpose of the paper is to provide beneficial references and experiences to facilitate the further curriculum construction and reform in higher school.

Ba0.6Sr0.4TiO3 (BST) thin films were fabricated by solgel technique on Pt/Ti/SiO2/Si substrate without and with PbO seeding layer from precursor solutions with different concentrations. The crystal structure, surface morphology, dielectric properties and leakage current density of BST thin films are investigated as functions of the concentration of PbO precursor solution. Its found that the growth orientation of BST thin films with PbO seeding layer can be modulated through adjusting the concentration of PbO precursor solution. BST thin film with PbO seeding layer from 0.05 M precursor solution shows the highest dielectric constant and tunability, which may be attributed to the high crystallization and amplitude of the polarization in high (100) preferred orientated films. The leakage current density of BST films increases with the increasing concentration of PbO precursor solution and agrees well with the space-charge-limited current mechanism at room temperature.

A steady thermal conduction model was presented to study the temperature field and thermal stress distribution in film irradiated by continuous wave laser. The thermal effects may arise from either the absorbing inclusions or the intrinsic absorption of film. Based on the plane thermal conduction assumption, the characteristics of damage resulted from local melting or evaporation and thermal stress were discussed. The damage region resulted from local melting or evaporation smaller than that from thermal stress. The circumferential stress σθis the main cause accounting for the stress damage. The normal stress perpendicular to the interface between film and substrate is the direct cause of drum type damage. The characteristics of damage in unsteady thermal conduction caused by pulse laser can be analyzed qualitatively by means of this model.

Context: MicroRNA (miR)-146b is overexpressed in papillary thyroid carcinoma (PTC) and is associated with extrathyroidal invasion, advanced tumor stage, and poor prognosis. However, the underlying mechanism of miR-146b in relation to its oncogenic behavior in PTC and its putative targets remain unknown. Objective: The purpose was to investigate IL-1 receptor-associated kinase 1 (IRAK1) as the potential miR-146b target gene and its involvement in PTC. Design: We used genome-wide microarray, computational analysis, and 3′ UTR reporter gene assays to identify IRAK1 as a miR-146b target gene. In vitro gain/loss-of-function experiments were further performed to determine the effects of IRAK1 on proliferation, colony formation, and wound-healing in PTC cancer cell lines. Expression levels of miR-146b and IRAK1 of 50 cases of PTC and its adjacent normal thyroid specimens were assessed via qRT-PCR. Results: Microarray expression profile revealed that the mRNA level of IRAK1 gene was down-regulated by miR-146b. The 3′ UTR of IRAK1 mRNA was found to be a molecular target of miR-146b posttranscriptional repression in BCPAP cells by reporter gene assays. MiR-146b promoted the migration and proliferation of PTC cells by down-regulating IRAK1 expression, whereas restoration of IRAK1 expression reversed this effect. In addition, the expression of IRAK1 mRNA was significantly lower in PTC clinical tissue samples than normal adjacent thyroid specimens and showed a strong inverse correlation with the expression of miR-146b in PTC specimens. Conclusion: Our results demonstrated that IRAK1 is a direct target of miR-146b and has functional roles to inhibit various aggressive PTC cell activities. In conjunction with current therapeutic regimens, targeting the miR-146b-IRAK1 axis may provide a potential approach for PTC management.

BZNT (Bi1.5Zn0.5Nb0.5Ti1.5O7) thin films were prepared on Pt/Ti/SiO2/Si substrates by radio frequency (RF) magnetron sputtering in different O2/Ar ranging from 4:16 to 7:13. The structure and surface morphology of BZNT thin films were investigated by x-ray diffraction (XRD) and atom force microscopy (AFM). The analysis of component in BZNT films were carried out by x-ray photoelectron spectroscopy (XPS). The dielectric measurements were conducted on metal-insulator-metal capacitors at the frequency from 100 Hz to 1M Hz. It’s found that the O2/Ar ratios significantly influence the elements content in BZNT thin films and the morphology and dielectric properties of BZNT thin films. At 1M Hz, the dielectric constant of BZNT thin films deposited at O2/Ar ranging from 4:16 to 7:13 is 212, 187, 171, 196, respectively. The BZNT thin film prepared at O2/Ar = 6:14 shows the highest figure of merit for its very low dielectric loss of 0.0024.

Bismuth zinc niobate titanium (Bi1.5Zn0.5 Nb0.5Ti1.5O7) (BZNT) thin films were deposited on PtTiSiO2Si substrates by radio frequency (rf) magnetron sputtering. The microstructure, surface morphology, stress, dielectric and tunable properties of thin films were investigated as a function of initial annealing temperature. It’s found that high initial annealing temperature increases the grain size, dielectric constant and tunability of BZNT films simultaneously and decreases the tensile stress in films. The BZNT thin film annealed from 500 °C to 700 °C shows the highest FOM value of 45.67 with the smallest dielectric loss and upper tunability.

Based on the surface morphology, a model is presented to investigate the heat transfer in anodic aluminum oxide (AAO) porous thin films. The extra thermal resistance from the micropores will inevitably cause a change in thermal properties, which can be analyzed by the Fourier law. The effect of the characteristic size on the thermal conductivity is discussed in details by means of the theory of phenomenological model of phonon scattering. Considering the effects of porosity and the distribution of micropores reflected by parameter D, the function of the effective thermal conductivity of AAO porous thin films expressed by two independent variables, εp and D. The temperature field is simulated with the effective thermal conductivity and the result demonstrates a bigger temperature rise in AAO porous thin films.

Transparent conducting aluminum-doped zinc oxide (AZO) films have been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target at different substrate temperatures. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall measurement, and optical transmission spectroscopy, and which were strongly influenced by substrate temperatures. Films with better texture, higher transmission, lower resistivity and larger carrier concentration were obtained for the samples fabricated at higher substrate temperature. The AZO film with the lowest resistivity of 4.63×10−4 Ω.cm and an average optical transmission of 92% in the visible range was deposited on the substrate heated at 450 °C. The optical bandgap depends on the deposition condition, and was in the range of 3.35~3.59 eV.

Background Tai chi (TC) is proposed as a potential option for the management of osteoarthritis (OA), however, its beneficial effect on patients with knee OA has not been convincing. Objectives To evaluate the effect of a 24-week TC program on physical functions in older Chinese women with knee OA. Methods Thirty-five older Chinese women with knee OA were randomized into TC group (n = 18) and attention control (wellness education and stretching) group (n = 17). Subjects in the TC group practiced the 24-form simplified Yang-style TC 2 to 4 times a week for 24 weeks with frequency gradually increased. Physical function was assessed using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC), 6-minute walk distance and stair climb time. Results Compared with the control group, the participants in TC group had statistically significant improvements in changes of the WOMAC total score (6.18 +/- 2.13 vs. 1.71 +/- 2.73, P = 0.000), the WOMAC pain subscale (1.36 +/- 0.22 vs. 0.07 +/- 1.00, P = 0.001), the WOMAC stiffness subscale (0.66 +/- 0.25 vs. 0.05 +/- 0.38, P = 0.043), the WOMAC function subscale (6.17 +/- 1.96 vs. 1.72 +/- 2.63, P = 0.000), the 6-minute walk distance (32.43 +/- 14.20 vs. 6.67 +/- 16.76, P = 0.003), and the stair climb time (2.27 +/- 0.74 vs. 0.27 +/- 1.24, P = 0.001). Conclusions This study suggests that TC provides a safe, feasible and useful exercise option for older Chinese female patients with knee OA.

Under the protection of argon gas, carbon nanotube reinforced magnesium metal matrix composite was made by stirring carbon nanotube into magnesium melts and formed by die casting. TEM and EDS methods were introduced to analyze boundary structure and chemical composition between carbon nanotube and magnesium metal matrix. The mechanical carbon nanotube properties of the composite were tested. Nickel chemical plating surface of carbon nanotube is favorable to adhesion of carbon nanotube to magnesium. Tests show that carbon nanotube, especially chemical nickel-plated one, has excellent role in strengthening the magnesium. The structure of magnesium was fined .The tensile strength, elongation, hardness and elastic modulus of the composite are improved.