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Multifunctional LiNbO3 material plays an important role in domain wall microelectronics and nonlinear optoelectronics. However, the material is hard and relatively inert, and hence is quite difficultly etched. A new oblique method to etch LiNbO3 memory cells at the surface of X-cut bulk crystals was proposed in this study. The process includes mask fabrication, oblique etching, and wet corrosion cleaning. The etching angle highly approaches 83° to achieve better polarization retention than others with etching angles of 0° and 70°. Meantime, the measured domain switching hysteresis loops become more symmetrical along the voltage axis than others with the presence of a strong imprint field. The horizontal electric field simulation along the polar Z axis exhibits the enhanced nucleating fields of the domains located at two edges of each memory cell in contact to Pt electrodes under the same applied voltage. The depolarization field was better screened in the memory with a higher etching angle. The new oblique method can improve the performance of the ferroelectric domain wall memory significantly.

In order to improve the parameter estimation accuracy of three-parameter Weibull distribution, a novel parameter estimation method using chaos simulated annealing particle swarm optimization (CSAPSO) algorithm is proposed. The simulated annealing (SA) algorithm is used to update the inertia weight of particle swarm optimization (PSO) algorithm according to the Metropolis acceptance criteria. The Chebyshev mapping is introduced into PSO according to the properties of chaos to make adaptively chaos mutate for premature particle. Moreover, in order to reduce the search range of PSO and improve the speed of parameter estimation, the initial estimation obtained by graphical parameter estimation method is taken as the initial solution of PSO. The proposed CSAPSO algorithm is compared with genetic algorithm (GA), PSO and SAPSO. These four algorithms are used to estimate the parameters of three sets of sample data which are conform to the Weibull distribution. The mean absolute percentage error (MAPE), correlation coefficient $$\rho $$ , Anderson Darling (AD) test value and the number of convergence step are used as evaluation indexes. The experimental results show that compared with the other three algorithms, the proposed CSAPSO algorithm has best parameter estimation accuracy for different number of samples and different setting parameters of three-parameter Weibull distribution.

Brain-derived neurotrophic factor (BDNF) is a growth factor that plays vital roles in the neuron survival, growth, and neuroplasticity. Alteration to BDNF expression is associated with major depressive disorder. However, the BDNF translational machinery in depression remains unknown. Herein, we pointed that Pdcd4, a suppressor oncogene, acted as an endogenous inhibitor for the translation of BDNF, and selectively repressed the translation of BDNF splice variant IIc mRNA in an eIF4A-dependent manner. Chronic restraint stress (CRS) up-regulated Pdcd4 expression in hippocampus via decreasing mTORC1-mediated proteasomes degradation pathway, which resulted in the reduction of BDNF protein expression. Moreover, over-expression of Pdcd4 in the hippocampus triggered spontaneous depression-like behaviors under the non-stressed conditions in mice, while systemic or neuron-specific knockout of Pdcd4 reverses CRS-induced depression-like behaviors. Importantly, administration of Pdcd4 siRNA or an interfering peptide that interrupts the Pdcd4-eIF4A complex substantially promoted BDNF expression and rescued the behavioral disorders which were caused by CRS. Overall, we have discovered a previously unrecognized role of Pdcd4 in controlling BDNF mRNA translation, and provided a new method that boosting BDNF expression through blocking the function of Pdcd4 in depression, indicating that Pdcd4 might be a new potential target for depressive disorder therapy.

One of the most important aspects in the field of dentistry is adhesion. Adhesion can be enhanced through different mechanisms, most commonly by chemical and mechanical modifications of dental material surfaces. One example of chemical adhesion utilizes primers or bonding agents containing coupling agents. Universal primers which are (mainly organophosphate-based monomers) and silane coupling agents are the most effective and most widely used for unifying dissimilar materials. Other than improving adhesion, Silanes have many other applications in dentistry. They have been found also to enhance the mechanical properties of materials either by adhesion or by becoming a constituent of dental materials itself. Universal primers, on the other hand, are utilized in bonding between different dental materials such as ceramics, metals, alloys, as well as to resin composites. Unfortunately, these primers, coupling agents, and bonding agents have, in general, poor hydrolytic stability. They are susceptible to humid oral environment, which invariably render them potentially unstable in the humid oral environment as saliva is always present. Improving their hydrolytic stability should therefore result in stronger adhesion for dental materials and dental prosthesis with a better clinical survival rate.

The aim was to evaluate in vitro the feasibility of using three silane coupling agents/blends: (I) 1.0 vol % 3-acryloxypropyltrimethoxysilane (ACPS), (II) a novel silane system: 1.0 vol % 3-acryloxypropyl trimethoxysilane + 0.5 vol % bis-1,2-(triethoxysilyl)-ethane (ACPS + BTSE), and (III) a novel silane system: 1.0 vol % 3-acryloxypropyl trimethoxysilane + 0.5 vol % bis[3-(trimethoxysilyl)propyl]amine (ACPS + BTMA), as adhesion promoters on the repair of dental silver amalgam with a resin composite with respect to various artificial ageing conditions. Two hundred and forty flowable composite resin stubs were bonded to freshly prepared dental silver amalgam discs. The discs were silica-coated and silanized with the 3 silanes. Another 20 resin stubs were bonded to the amalgam surface without any silica-coating or treated with silica-coating only. Then, the specimens were randomly distributed into 8 sub-groups for initial (control), thermal cycling (1000, 3000 and 6000) and DI water storage (1 day, 1 week, 1 month and 3 months). Shear bond strength (SBS) test was measured using a universal testing machine with a 1 mm/min cross-head speed. Failure modes were classified and SEM images were obtained. Two-way ANOVA was used to detect statistical differences. The initial SBS of the control groups were (Mean/SD) 20.2 ± 3.3 MPa for ACPS only, 16.6 ± 3.9 MPa for ACPS + BTMA, and 19.5 ± 3.3 MPa for ACPS + BTSE. A decreasing trend of SBS was observed by using the current artificial ageing methods, and ACPS and ACPS + BTSE produced statistically higher bond strengths compared to ACPS + BTMA under thermal cycling (p

During plasma spray-physical vapor deposition (PS-PVD) of yttria-stabilized zirconia (YSZ) coatings, evaporation of the YSZ powder is essential, but quite difficult when using a commercial

In order to accurately estimate the anti-penetration capacity of yaw-inducing bursting layer with irregular barriers on surface impacted by projectile, the theoretical model of attack angle and angular velocity for projectile impacting on irregular barrier was achieved according to the macroscopic relation of contact force versus contact time, in which the main factors such as the relative geometrical characteristics of projectile and irregular barrier, material property and impact velocity of projectile influencing on yaw-inducing effectiveness were considered. On the basis of considering synthetically the influences of attack angle, impact velocity, impact angle of projectile and uncontrolled free surface of target, the theoretical formulation of penetration depth for bursting layer with irregular barriers on surface impacted by projectile was presented by expressing the stress of an optional point on the nose of projectile according to the relation of stress versus velocity. The theoretical results indicate that in the case of oblique impact embodying effect of attack angle, the penetration depth is reduced with the increase of impact angle, attack angle or angular velocity, and penetration trajectory is also deflected obviously. The effectiveness of angular velocity influencing on penetration depth is increased with impact velocity increasing. The theoretical results are in good agreement with test data for low impact velocity.

Objective: The study was to observe the effect of polymer-PS (Curosurf)mixtures on acute lung injury rats with E.coli. Methods: Adult rats given 3ml/kg 3x109CFU/ml E.coli by tracheal, were mechanically ventilated after infection for 24~36h. Fifteen minutes later, the animals with ALI (PaO2 < 20.kPa) were randomly divided into six treatment groups by transtrachea instillation (1) NS group (2) PS group (3) PS+NS group (4) PS+ PEG group (5) PS+ Dextran group (6) PS+ HA group. The blood gas analysis were measured in the pre-or post-treatment during 180 min. At the end, MIP-2 in the right lung lavage fluid were performed. Result: At 180 min post-treatment, PaO2 of all PS or PS-polymer treatment groups increased compared with pre-treatment, but they were less than normal control group (p< 0.01), PaO2 of PS, PS+ Dextran, PS+HA group were singnificantly more than that of the NS group (p< 0.01 or 0.05) respectively. MIP-2 of lung lavage fluid in all treatment groups were higher than that of normal group (p< 0.01 or 0.05). MIP-2 of PS, PS+PEG, PS+ Dextran, PS+ HA group were less than that of NS group (p< 0.01) respectively except PS+NS group. Conclusions: The data suggest that PS, PS+Dextran and PS+HA improved oxygenation function in ventilated rats with ALI induced by E.Coli. and the PS-polymer mixtures seemed more effective in inhibiting MIP-2 than PS in the same dose. Further preclinical studies are required.