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Effect of intermediate thermomechanical treatment on tensile properties at short-transverse direction, fracture mechanism and microstructure of 2A97 Al-Li alloy thick plate were studied by tensile testing, SEM, EBSD and TEM.The results show that with the increasing of compression deformation, the strength and elongation of the alloy increase first and then decrease slightly. The fracture mode of the alloy changes from quasi-cleavage fracture to high energy ductile fracture. When the compression deformation rises to 20%, the elongated structure are replaced by a more uniform and equiaxial structure. The distribution of δ phase distribute more homogeneously in the grains.

The effect of solution temperature on the solid solubility, microstructure and mechanical properties of 2A66 Al-Cu-Li alloy was studied by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and tensile test. The results show that with the solution temperature increasing from 480°C to 520°C,the amount of residual phases decreased and the solid solubility increased obviously, while the recrystallization hardly changed with the increasing of solution temperature. With the solution temperature increased to above 530°C, the amount of residual phases almost did not change. With the solution temperature increasing to above 540°C, the alloy was over-burnt obviously. Complete dissolution of the particles in the 2A66 Al-Cu-Li alloy was obtained after solution treatment at 520°C.

The effect of rolling process on the mechanical property and microstructure of 2A66 Al-Li alloy sheet was investigated. Three different rolling processes for 2A66 AL-Li Alloy Sheet were picked for fatigue crack growth test in T3. The results showed that enhancing the amount of deformation in the range of moderate or reducing the rolling step of rolling process will increase the fatigue crack growth rate.

The microstructure evolution during homogenization of 2A66 Al-Cu-Li alloy was investigated by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM) and differential scanning calorimeter (DSC). The results showed that the dendritic segregation can be found in the ingot of experimental alloy. Numerous eutectic phases can be observed in the grain boundary, and the distribution of the main elements along the interdendritic region varied asymmetrically. It was found that the main secondary phase was Al2Cu. Differential scanning calorimeter (DSC) results showed that the over-burnt temperature of 2A66 Al-Cu-Li alloy was 515°C. With the increase of homogenization temperature in the area of 480°C~510°C, the boundaries of experimental alloy became sharp and the most of secondary phase dissolved into the matrix. The experimental alloy heat treated at 520°C was over-burnt. The Al3Zr precipitated and α (Al) super-lattice was observed by TEM in the experimental alloy after homogenization.

The microstructure and tensile properties of permanent-mould cast Mg-5wt%Sn-4wt%Cu alloy was investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and tensile test in this paper. The result indicated that the microstructures of the as-cast samples consist of 30-40 μm size primary solidification phase, primary dendrite Mg2(Cu,Sn) which is a network-like interdendritic eutectic intermetallic compounds along grain boundaries and particle like Mg2(Sn,Cu) phases. The Mg-5Sn-4Cu alloy exhibit maximum ultimate tensile strength and yield strength, and the values are 142 MPa and 91 MPa at room temperature. This improved mechanical property is mainly ascribed to the formation of network-like secondary phases of primary dendrite Mg2(Cu,Sn).

With the in-depth study on the blast furnace iron-making process and the operational characteristic of auxiliary materials in iron-making process, the comprehensive coke rate’s main influencing factors based on the operation characteristics of auxiliary materials were found. Then, a BP neural network model was used to simulate the mathematic mapping relationship between comprehensive coke rate and main influencing factors. Based on the established BP neural network model, through setting the comprehensive coke rate lowest as the goal and using the actual production data of a iron &steel company’s 6# blast furnace ,a genetic algorithm method is adopted to find the best optimal combination among the main influencing factors. The results show that after optimization calculation the comprehensive coke rate could be reduced about 35.85kg. A new perspective and a scientific method are proposed to realize the target of energy conservation and emission reduction in ironmaking process in this paper.

Rho kinase (ROCK) was the first downstream Rho effector found to mediate RhoA-induced actin cytoskeletal changes through effects on myosin light chain phosphorylation. There is abundant evidence that the ROCK pathway participates in the pathogenesis of retinal endothelial injury and proliferative epiretinal membrane traction. In this study, we investigated the effect of the ROCK pathway inhibitor Y-27632 on retinal Müller cells subjected to hypoxia or oxidative stress. Müller cells were subjected to hypoxia or oxidative stress by exposure to CoCl2 or H2O2. After a 24-hour treatment with Y-27632, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was used to assess the survival of Müller cells. Hoechst 33258 was used to detect apoptosis, while 2′,7′-dichlorodihydrofluorescein diacetate was used to measure reactive oxygen species generation. A transwell chamber system was used to examine the migration ability of Müller cells. Western blot assay was used to detect the expression levels of α-smooth muscle actin, glutamine synthetase and vimentin. After treatment with Y-27632, Müller cells subjected to hypoxia or oxidative stress exhibited a morphology similar to control cells. Y-27632 reduced apoptosis, α-smooth muscle actin expression and reactive oxygen species generation under oxidative stress, and it reduced cell migration under hypoxia. Y-27632 also upregulated glutamine synthetase expression under hypoxia but did not impact vimentin expression. These findings suggest that Y-27632 protects Müller cells against cellular injury caused by oxidative stress and hypoxia by inhibiting the ROCK pathway.

To investigate the effect of lentivirus-mediated integrin-linked kinase (ILK) RNA interference (RNAi) on human retinal Müller cells transdifferentiation into contractile myofibroblasts.A lentiviral vector expressing ILK-specific shRNA was constructed and introduced into cultured retinal Müller cells. Silencing of the ILK gene was identified by real time RT-PCR and Western blot. The Müller cell phenotype change was confirmed by immunodetection of alpha-smooth muscle actin (alpha-SMA) stress fiber formation. The generation of tractional force was assessed using a tissue culture assay with cells incubated in three-dimensional collagen gels; cell migration was determined by the Boyden chamber method, using 10% FBS as a chemotactic factor.Significant decreases in ILK mRNA and protein expression were detected in Müller cells carrying lentiviral ILK-shRNA vector. Cells treated with anti-ILK siRNA showed less alpha-SMA stress fiber formation under hypoxic conditions or cell subcultivation. Lentiviral ILK-shRNA vector transfection also significantly reduced cell migration and cell-mediated gel contraction.Lentivirus-mediated ILK RNAi decreased cell migration and contractile force generation by inhibiting alpha-SMA stress fiber formation in human retinal Müller cells. This tool might be useful to treat ocular fibroproliferative diseases associated with transdifferentiated Müller cells.

The aim of the study was to evaluate the outcome of adenovirus-mediated p27KIP1 (Ad-p27) expression on wound healing after filtration surgery and to investigate the inhibition of cell proliferation induced by Ad-p27. We constructed the adenovirus recombinant vector Ad-p27 and administered it to a rabbit model of glaucoma filtration surgery by subconjunctival injection; phosphate-buffered saline (PBS) and mitomycin C (MMC) were used as controls. Intraocular pressure (IOP), bleb scores, and anterior chamber depths were observed during a 28-d period. Histological examinations, fluorescence observations and Western blot analyses were evaluated. Ad-p27 enhanced the surgical outcome and inhibited cell proliferation when compared with PBS. Bleb scores in the Ad-p27-treated eyes were higher than those in the PBS-treated eyes on d 7 (P

Objective To investigate the role the lens dimensions played on the pathogenesis of primary angle-closure glaucoma. Methods 38 eyes of 20 patients with primary angle-closure glaucoma(PACG) and 35 eyes of 22 normal individuals without ocular abnormalities were examined. The anatomical parameters of the lens and other structures of the anterior segment were calculated using B ultrasound, computer image processing and ultrasound biomicroscopy(UBM). The parameters were compared between the patients and normal subjects. Correlation analysis was used to determine the relationship between the radii of curvature of the anterior lens surface(RCALS) and the other parameters of the anterior segment. Results Compared with the normal eyes, the eyes of PACG had thicker lens, steeper curvature of anterior lens surface, decreased depth of the anterior chamber, narrower chamber angle, and more anterior position of the ciliary bodies and lens. All these differences were significant(P Conclusion The occurrence of PACG is relevant to the abnormal anatomical structures of the anterior segment. Among all factors, the lens parameters play an important role in the pathogenesis. Increased lens thickness, relative more anterior position of lens, especially steepened curvature of anterior lens surface are predisposing factors of the pathologic phenomenon in PACG including pupillary blockage, shallow anterior chamber, secondary closure of chamber angle and elevation of intraocular pressure.

To investigate the interfering effect of Y-27632, a ROCK-I selective inhibitor, on the signal transduction pathway of transforming growth factor-β1 (TGF-β1) in ocular Tenon capsule fibroblasts (OTFS) in vitro.After OTFS from passages 4 to 6 in vitro were induced by TGF-β1 and then treated by Y-27632, the changes of the OTFS cell cycles were analyzed via flow cytometry, and the proteins expression of the α-smooth muscular actin (α-SMA), connective tissue growth factor (CTGF), collagen I were calculated by Western blot. After OTFS treated by the different concentrations of Y-27632, the expression levels of the α-SMA, CTGF and collagen I mRNA were assayed by RT-PCR.Y-27632 had no markedly effect on the OTFS cell cycles. After treated by TGF-β1, OTFS in G1 period significantly increased. The cell cycles distribution by both TGF-β1 and Y-27632 had no remarkable difference from that in control group. Y-27632 significantly inhibited the proteins expressions of both α-SMA and CTGF, while to some extent inhibited that of collagen I. TGF-β1 significantly promoted the proteins expressions of α-SMA, CTGF and collagen I. After OTFS treated by both TGF-β1 and Y-27632, of α-SMA, the protein expression was similar with that in control group (P=0.0660.05), but the protein expression of CTGF or collagen I, respectively, was significantly different from that in control group (P=0.0000.01). The differences of expressions of the α-SMA, CTGF and collagen I mRNA in 30, 150, 750µmol/L Y-27632 group were statistically significant, compared with those in control group, respectively (α-SMA, P=0.002, 0.000, 0.000; CTGF, P=0.014, 0.002, 0.001; collagen I, P=0.003, 0.002, 0.000).Blocking the Rho/ROCK signaling pathway by using of Y-27632 could inhibit the cellular proliferation and the expression of both CTGF and α-SMA whatever OTFS induced by TGF-β1 or not. Y-27632 suppressed the expression of collagen I mRNA without induction.

Firstly, relying on the science and technology project of high yield in Hebei Province, connotation of agricultural technology demonstration and extension modes and the grain yield project in Hebei Province is introduced. Extension mode of agricultural technology demonstration and radiation is constructed. Agricultural technology demonstration and radiation mode includes the radiation center, primary irradiation and secondary irradiation. Secondly, management system and operational mechanism of agricultural technology demonstration and radiation mode are discussed, mainly expressed in establishing leading group of demonstration counties (cities), implementing responsibility system of department leaders, setting up expert advisory instruction group, subject technology expert group and the leading group of radiation zone, carrying out the chief expert responsibility system and the technicians matrix responsibility system, establishing the operating mechanism of “open, flow, competition and collaboration” with "test area — expert two-way selection " as the core content. Finally, countermeasures to improve the agricultural technology demonstration and radiation model is put forward, such as establishing the rural technology and demonstration base, strengthening cooperation with enterprises, and adopting flexible technical training, so as to promote the communication of agricultural high-tech, to increase the contribution rate of agricultural technology, and to offer ideas for agricultural extension model at the new era.