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Exocyst complex component 3 Sec6 of mammals, one of the components of the exocyst complex, participates in numerous cellular functions, such as promoting cell migration and inhibiting apoptosis. In this study, the Sec6 was obtained from Epinephelus coioides, an economically important cultured fish. The full length of E. coioides Sec6 was 2655 bp including a 245 bp 5' UTR, a 154 bp 3' UTR, and a 2256 bp open reading frame (ORF) encoding 751 amino acids, with a molecular mass of 86.76 kDa and a theoretical pI of 5.57. Sec6 mRNA was detected in all the tissues examined, but the expression level is different in these tissues. Using fluorescence microscopy, Sec6 were distributed in both the nucleus and the cytoplasm. After SGIV infection, the expression of E. coioides Sec6 was significantly up-regulated in both trunk kidney and spleen response to Singapore grouper iridovirus (SGIV), an important pathogens of E. coioides. Sec6 could increase the SGIV-induced cytopathic effects (CPE), the expression of the SGIV genes VP19, LITAF, MCP, ICP18 and MCP, and the viral titers. Besides, E. coioides Sec6 significantly downregulated the promoter of NF-κB and AP-1, and inhibited the SGIV-induced apoptosis. The results demonstrated that E. coioides Sec6 might play important roles in SGIV infection.

Heat shock proteins (Hsps) are important for maintaining protein homeostasis and cell survival. In this study, Hsp27 of Epinephelus coioides, an economically important marine fish in China and Southeast Asian countries, was characterized. E. coioides Hsp27 contains the consered ACD_HspB1_like domain and three p38 MAPK phosphorylation sites, located at Thr-13, Thr-60 and Ser-167. E. coioides Hsp27 was distributed in both the cytoplasm and nucleus, its mRNA was detected in all 14 tissues examined, and its expression was up-regulated after challenge with Singapore grouper iridovirus (SGIV), an important E. coioides pathogen. Over-expression of E. coioides Hsp27 significantly upregulated the expressions of the key SGIV genes (VP19, LITAF, MCP, and ICP18), downgraded the expressions of the E. coioides immune factors (IRF3, IRF7, ISG15, and TRAF6) and proinflammatory factors (TNF-α, IL-8), downgraded the activation of nuclear factor kappa-B (NF-κB) and activator protein-1 (AP-1), and substantially inhibited the cell apoptosis induced by SGIV infection. These data illustrated that E. coioides Hsp27 might be involved in SGIV infection by negatively regulating the innate immune response.

Synthetic aperture radar (SAR) Image containing the coherent speckle noise, traditional methods can't very well to SAR image segmentation, based on SAR image grayscale distribution model, this paper proposes a combination of pixel gray level and area information of the image segmentation method. First of all, based on SAR image in all kinds of feature of gray histogram presents the facts of the Rayleigh distribution, fitting of image gray level of probability density distribution; Then use fuzzy biggest office methods select the optimal threshold, and the resulting statistics as the related parameters of image, the image blur ; Then to 3 x3 neighborhood pixels within the membership degree of fuzzy characteristics of Kohonen self-organizing map neural network is adopted to improve the coarse segmentation, the segmentation of noise and boundary classes pixels using a region growing technique relaxation iteration to fine segmentation.

The machining methods such as waterjet cutting, milling, grinding, lapping, etc. are usually used to manufacture glass fiber reinforced composites (GFRCs) parts. Damages will be produced unavoidably in the machining process, no matter which machining method is employed. Subsurface damage is one of the important parameters to evaluate the surface layer damages. The detection method for the subsurface damages of glass fiber reinforced glass matrix (glass/glass) composite after machining is researched. The characteristics of subsurface damages of glass/glass composite after waterjet cutting, milling, grinding and lapping are investigated mainly, when the fiber direction is either perpendicular or parallel to the cutting surface.

Superalloys are widely used in the aeronautic and astronautic industries owing to their excellent properties in aspects of high-temperature strength, heat stability and thermal fatigue resistance. However, the severe loading of grinding wheel and the poor integrity of grinding surface usually become the problem in grinding of superalloys with conventional grinding wheels. In this paper an experimental study was carried out to investigate the grinding characteristics of superalloys with microcrystalline alumina abrasive wheel. The roughness of grinding surface was tested, on which the effects of the grinding parameters were analyzed. Study results indicated that low loading of grinding wheel and high quality of grinding surface (Ra 0.2 μm) were obtained. The grinding parameters were optimized based on the experiment results.

This study presents design of an ultra-precision wafer grinder which incorporates state-of-the-art automatic supervision and control system. The wafer grinder is characterized by wafer surface shape control, grinding forces and wafer thickness monitoring systems. The design provides a totally integrated solution to the ultra-precision grinder that is capable of grinding silicon wafers with surface roughness Ra

Silicon wafers are widely used in integrated circuits. This article addresses an important aspect of flat wafer grinding: grinder design. An advanced grinder with two-spindle and three-workstation for ø300 mm silicon wafer based on the principles of in-feed grinding was successfully developed. A mathematical model on topography control was developed for the first time to provide a totally integrated solution for dressing chuck with given topography. The developed model was then applied to predict the chuck topography or to adjust the obliquity adjustment device according to the parameters of ground chuck. Finally, the pilot experiments on two groups of chucks, which demonstrate the correctness of topography control are included.

A Novel Piezoelectric Grinding Dynamometer for Monitoring Ultra-precision Grinding of Silicon Wafers

Grinding forces during grinding silicon wafer have great influences on the accuracy, surface quality and grinding yield of the wafer. It is necessary to develop an accurate and reliable grinding dynamometer for measuring and monitoring the grinding process of the large and thin wafer. In this work, a new 3D (three-dimensional) grinding dynamometer using piezoelectric sensors is designed and developed, which is used for a wafer grinder based on wafer rotating grinding method. The calibrating experiments of the 3D grinding dynamometer are carried out. The FEA and modal analysis are made and compared with the results of mode testing. Furthermore, the static performance parameters of the dynamometer are obtained from the loading experiment. The experiment results indicate that the 3D grinding dynamometer can measure axial, radial and tangential grinding force of grinding wheel with high sensitivity, good linearity, good repeatability and high natural frequency, and fully satisfied requirement for measuring and monitoring of the grinding force in wafer grinding process.

The signal identification technology is applied in tertiary recovery of oil field, which is based on that everything has own resistivity. The artificial physical models are established basis on the heterogeneity of Daqing oilfield main oil layers. The matrix of reservoir does not conduct electricity, but the water with salt in the reservoir can. So the electrodes are inserted in the physical model according to some regulars in the process of polymer flooding experiment. The change of resistivity can reflect the front movement of oil and water with different time, so the distribution with water and oil saturation, sweep efficiency can be obtained. The experiments are done with one dimension and three dimensions heterogeneous physical model interlayer or intraformational layer respectively. The polymer solutions are compound with 1500mg/L KCl high salinity water. The experimental results show that the front of polymer solutions can be recognized with this method. The sweep efficiency is 0.92 and 0.67 in the medium and low permeability interlayers model with 570mg/LPV polymer solutions, the sweep efficiency of medium and low permeability intraformational heterogeneity model is 0.83 and 0.34 simultaneity, the time when the polymer has effect is later than interlayer model, the total recovery is also lower than interlayer model 2.63%. This paper will help study the macro movement laws of oil and water, micro percolation mechanics and residual oil distribution with experiment technology. This study further extends the technology application between cross subjects.