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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.

Modular multilevel converter (MMC) has great prospects in voltage source converter-based high-voltage direct current (HVDC) transmission. Although the typical half-bridge MMC can bring huge economic benefits, it is unable to clear dc fault. An MMC based on arm transfer (AT-MMC) and corresponding timing control are presented to effectively solve this drawback. Compared with the half-bridge MMC, the AT-MMC adds the arm-transferring branch to the each phase unit of the converter and adds the current-breaking branch and the energy-absorbing branch to the dc line. Through these branches cooperating with each other, the fault current is cleared. Referring to the half-bridge MMC with the same voltage grade, the AT-MMC has a good economy and its additional device cost is low and additional conduction loss is very small. A model of 51-level MMC–HVDC system is built in RT-LAB OP5600 to verify the effectiveness of the proposed solution.

Depression is one of the most common psychiatric disorders. Recently, studies demonstrate that antidepressants generating BDNF not only maintain synaptic signal transmission but also repress neuroinflammatory cytokines such as IL-6 and IL-1β. Therefore, promoting BDNF expression provides a strategy for the treatment of depression. Our recent research has indicated that programmed cell death 4 (Pdcd4) is a new target for antidepressant treatment by facilitating BDNF. Herein, we modified Pdcd4 specific small interfering RNA (siPdcd4) with the rabies virus glycoprotein peptide (RVG/siPdcd4) which enables it cross the blood-brain barrier (BBB). We found that RVG/siPdcd4 complex was selectively delivered to neurons and microglia and silenced the expression of Pdcd4, thereby up-regulating the level of BDNF and down-regulating IL-6 and IL-1β expression. More importantly, RVG/siPdcd4 injection attenuated synaptic plasticity impairment and protected mice from CRS-induced depressive behavior. These findings suggest that RVG/siPdcd4 complex is a potential therapeutic medicine for depression.

In the influencing factors of reading distance of RFID tags, the tags’ geometric spatial structures have an important aspect on the corresponding reading distance. In order to achieve the goal of improving the reading distance of RFID tags, a novel three-dimensional (3D) position measurement and structure prediction method for RFID tag group based on deep belief network (DBN) is proposed. First, a 3D structure prediction system for RFID tags, which is based on stereovision, is designed. Second, an image deblurring scheme which combines the knife-edge with Wiener filtering method is adopted to restore the blur image in the 3D position measurement process. Then, RFID tags’ 3D positions are acquired by using the image matching method. Finally, the relationship model between RFID tags’ 3D positions and reading distance is built by DBN. The experimental results show that the relationship between tag group’s 3D positions and reading distance can be well built by DBN. The established DBN can forecast the reading distance accurately. The MAPE and RMSE of DBN prediction results are 1.64% and 0.168. The DBN can find the best 3D spatial distribution structure of RFID tag group corresponding to the maximum reading distance, which can guide the 3D distribution of the tag group.

Objective Numerous bond strength tests have been performed on dental adhesion experiments. Yet, the validity of these bond strength tests is controversial due to the name ( e.g. , “shear” or “tensile”) may not reflect to the true and complete stress situation, i.e. , assumed uniform shear or uniaxial tensile conditions. Thus, the aim of this study was to simulate and compare the stress distribution of and between shear bond strength (SBS), tensile bond strength (TBS), mold-enclosed shear bond strength (ME-SBS) and de novo lever-induced mold-enclosed shear bond strength (LIME-SBS) tests. Methods 3-Dimensional finite element method (FEM) was used on the dental resin-bonded surfaces ( i.e. , titanium alloy, dentine and porcelain) interphased with adhesive layer (thickness 5 μm) to simulate the mechanical tests. For ME-SBS, both polycarbonate and stainless steel molds were used. For LIME-SBS, stainless steel levers and molds with lengths of 3 mm, 6 mm, 12 mm, 15 mm and 18 mm were used. The applied loads on these models were 50 N, 100 N and 200 N. Results De novo LIME-SBS test was the most optimal configuration to evaluate “shear” bond strength of adhesive in regards to providing significantly high and uniform shear stress as well as eliminating tensile stress at the interface. The conventional SBS test created very high tensile stress at the load area, whereas the TBS created optimal tensile stress but shear stress indeed co-exist. The ME-SBS test could also eliminate some of the tensile stress. Similar stress distributions pattern appeared on the Ti-adhesive models, the dentine-adhesive models and porcelain-adhesive models. Significance None of the bond strength tests could give purely “shear” or “tensile” bond strength, but LIME-SBS seems to be the best model to evaluate the bond strength under true “shear” mode.

Recently, the discriminant learning denoising model has deserved special attention due to its outstanding denoising property. This paper designs the RFID multi-label dynamic localization system based on visual measurement to avoid electromagnetic interference. Firstly, the potential sharp images are estimated via denoising images acquired by dual CCD. Then the labels are matched by template. Finally, Shaft Alignment Method (SAM) models the multi-label 3D coordinates in world space and image pixel. Flexible Feed-forward Denoising Convolutional Neural Network (FDnCNN) is proposed to reach the equilibrium between denoising effect and image particulars without producing artifacts in GPU effectively and flexibly. FDnCNN increases the image quality by at least 0.5 dB than WNNM and DnCNN. The 3D coordinate measurement system is evaluated by error, which proves the feasibility and effectiveness of the positioning system.

Sensitivity is an important indicator for evaluating the performance of RFID tag. Firstly, this paper gives the definition of group tags sensitivity. Furthermore, the formula of the group tags sensitivity is deduced. Secondly, Semi-physical verification platform is used to measure the reading distance of the tags. Thirdly, the sensitivity for each tag in the tags group is tested. Finally, the group tags sensitivity is obtained and calibrated. The experimental results show that the formula accords with the actual result. Therefore, this work is very useful for dynamical measurement and calibration for RFID tags group sensitivity.

In RFID multi-tag network, the image of the tag needs to be collected. Therefore, the research on the effect of LED array light source on the image capture of RFID tag is proposed. According to the optical properties of LED, the radiance illumination expression of LED array light source is deduced, and the illumination distribution of LED array is simulated. We choose the appropriate arrangement of array light sources and analyze the effect of the array on the collection of the tags. The research results show that the LED array design can effectively provide a uniform illumination of the light source. The design of LED array can obviously distinguish the tag from the background and improve the quality of the acquired RFID tag image.

With the aging rate picking up speed, demand for social care services rising, pension and real estate gradually become an important form for solving the pension problem. But pension real estate is a combination of old-age pension services and real estate, which combines both the advantages of real estate and pension services, with strong composite capability and quite wider scale. And therefore, it is facing great difficulties and challenges on the operational financing. Based on the specific attributes of pension real estate, pointing out the necessity for PPP model applied on the pension real estate projects at present. First, using SWOT to decompose pension estate PPP mode encountered the internal strengths, weaknesses, external opportunities and potential threats. Then use AHP (analytic hierarchy process) to quantify the results of the survey, and advising to select much more good Pension PPP model for real estate projects, let real estate projects in PPP mode to make pension application decisions more scientific and targeted.

nbsp nbsp Background It is still difficult to perform pedicle screw insertion on patients with abnormal spine morphology There is an urgent need to provide projection fluoroscopy images to surgeons to practice pedicle screw insertion nbsp nbsp Methods The simulation software uses a volume rendering algorithm to generate a three dimensional spine and it uses a digitally reconstructed radiograph algorithm to simulate anteroposterior and lateral radiographs as the intraoperative image for minimally invasive surgery nbsp nbsp Results Pedicle screw insertion can be accomplished using a bone drill and multidimensional pedicle screws and can be exhibited or evaluated in both two and three dimensions Simultaneously advanced expert preoperative planning can be shown in system nbsp nbsp Conclusion A simulator that develops a three dimensional patient specific volume rendered simulation combined with the projection fluoroscopy for pedicle screw insertion is introduced The simulator can help the surgeon to plan the operation trajectory and can help to predict the complex situation of the operation

Three-phase rectifier voltage often use software phase-locked loop, input voltage is appropriate. However, the software phase-locked loop had previously most locks can only perform accurate voltage in order that agreement cannot be done accurately lock in reverse order (lost key). To overcome this drawback in this article combines the principle of phase locked loop voltage argued upon, examined the nature of change of voltage vector angle reverse order, analyze the causes loss of lock reverse order part of a program to design self-adaptive phase locked loop can be done in the correct key sequence voltage and voltage upon reverse order. Also in this article also offer solutions using fractional integrated controller PIX to improve software self-adaptive phase locked loop instead of using the traditional PI controller as the software was designed before. Experimental results have demonstrated the method using fractional controllers to improve software PI phase locked loop three-phase self-adaptive software makes the phase locked loop to work more flexible, done properly locked voltage law in order upon agreement or otherwise. Carry extra one further step, analysis and experiments demonstrated using software adapts phase locked loop can make PWM (pulses width modulation) rectifiers work without influenced by the phase sequence of input voltage.

OBJECTIVE To evaluate whether the combination of magnetic resonance spectroscopy (MRS) and ¹¹C-methionine positron emission tomography (¹¹C-MET PET) could increase accurate diagnostic sensitivity for non-enhancing supratentorial gliomas. MATERIALS AND METHODS Between February 2012 and December 2017, 109 patients with non-enhanced supratentorial lesions on contrast-enhanced MRI were enrolled. Each patient underwent MRS and ¹¹C-MET PET before treatment. A lesion was considered to be a glioma when either the MRS or ¹¹C-MET PET results reached the diagnostic threshold. The radiological diagnosis was compared with the pathological diagnosis or medical diagnostic criteria. RESULTS The sensitivity and specificity were 60.0% and 50.0% for MRS and 75.8% and 50.0% for ¹¹C-MET PET, respectively. Upon combining the two modalities, the sensitivity and specificity of the imaging-based diagnosis prior to surgery reached 89.5% and 42.9%, respectively. Statistically significant differences in the sensitivities were observed between the combined and individual approaches (MRS alone, 89.5% vs. 60.0%, p < 0.001; ¹¹C-MET PET alone, 89.5% vs. 75.8%, p = 0.001). However, no significant differences in specificity were observed between the combined and individual modalities. CONCLUSION The combination of MRS and ¹¹C-MET PET findings significantly increases accurate diagnostic sensitivity for non-enhancing supratentorial gliomas without significantly lowering the specificity. This finding suggests the potential of the combined MRS and ¹¹C-MET PET approach in clinical applications.

To realize the target of having a precise feature size measurement of multihole sheet metal part, this paper based on HALCON, first calibrates the camera with HALCON's calibration assistant. After acquiring the image of the multihole sheet metal part, the image coordinates of the center of fitting ellipse and the length of the long and short half shaft (pixel unit) can be gotten by proceeding a series of operations like thresholding, subpixel-precise contour extraction, fitting ellipses and so on. At last, the point coordinates in image are transformed into the plane Z=0 of the world coordinate system through translation and rotation, and the value of each feature size of the sheet metal part can be calculated.

This paper utilized an intelligent vehicle model for the “Freescale” Cup National College Students' Intelligent Vehicle competition as the main study object. Under the prerequisite of adopting the same control procedures and algorithms, the mechanical structures and its parameters of the model vehicle which influence the running performance, such as front wheel alignment, steering mechanism and rear wheel deceleration mechanism are optimally designed and adjusted .It has been proved that the scheme induced the model vehicle driving fast and stable on the path-complex track and thus to achieve reasonable effects.

Objectives: This study aimed to review etiological and epidemiological data for hand, foot, and mouth disease (HFMD) cases that occurred between 2008 and 2010 in Guangzhou City, to help develop and implement precautionary measures applicable for future outbreaks. Methods: The characteristics of 4,753 HFMD episodes were retrospectively reviewed in 4,636 patients reported between 2008 and 2010 by the Guangdong Women and Children's Hospital, which is the national enterovirus monitoring agent and the designated hospital in China for treating severe HFMD. Results: Out of 4,753 incident episodes reviewed, 525 patients were hospitalized; 60% were males. Most patients (93.8%) were children under 5 years old, with a median age at onset of 2.4 years. HFMD incidence peaked in April/May and September/October. From the total, 1,067 (22.4%) infections were positive for human enterovirus 71 (HEV71), 1,094 (23.0%) were positive for coxsackievirus A16 (CA16), and 941 (19.8%) were positive for other common enteroviruses. In contrast, 1,666 (35.0%) cases were negative to HEV71, CA16, and other common enteroviruses. Cross-correlation coefficients demonstrated associations between the number of cases, seasonal temperatures, and humidity. Among hospitalized cases, HEV71 was positive in 261 (24.5%), and 42 (3.9%) critical cases were positive for HEV71. Conclusion: Seasonal fluctuations and HEV71 and CA16 were the two key factors influencing the Guangzhou HFMD epidemic. The infection predominantly affected children younger than 5 years old. Keywords: Epidemic, Hand, foot and mouth disease, Coxsackie virus A16, Human enterovirus 71

OBJECT The extent of resection is one of the most essential factors that influence the outcomes of glioma resection. However, conventional structural imaging has failed to accurately delineate glioma margins because of tumor cell infiltration. Three-dimensional proton MR spectroscopy (1H-MRS) can provide metabolic information and has been used in preoperative tumor differentiation, grading, and radiotherapy planning. Resection based on glioma metabolism information may provide for a more extensive resection and yield better outcomes for glioma patients. In this study, the authors attempt to integrate 3D 1H-MRS into neuronavigation and assess the feasibility and validity of metabolically based glioma resection. METHODS Choline (Cho)–N-acetylaspartate (NAA) index (CNI) maps were calculated and integrated into neuronavigation. The CNI thresholds were quantitatively analyzed and compared with structural MRI studies. Glioma resections were performed under 3D 1H-MRS guidance. Volumetric analyses were performed for metabolic and structural images from a low-grade glioma (LGG) group and high-grade glioma (HGG) group. Magnetic resonance imaging and neurological assessments were performed immediately after surgery and 1 year after tumor resection. RESULTS Fifteen eligible patients with primary cerebral gliomas were included in this study. Three-dimensional 1H-MRS maps were successfully coregistered with structural images and integrated into navigational system. Volumetric analyses showed that the differences between the metabolic volumes with different CNI thresholds were statistically significant (p < 0.05). For the LGG group, the differences between the structural and the metabolic volumes with CNI thresholds of 0.5 and 1.5 were statistically significant (p = 0.0005 and 0.0129, respectively). For the HGG group, the differences between the structural and metabolic volumes with CNI thresholds of 0.5 and 1.0 were statistically significant (p = 0.0027 and 0.0497, respectively). All patients showed no tumor progression at the 1-year follow-up. CONCLUSIONS This study integrated 3D MRS maps and intraoperative navigation for glioma margin delineation. Optimum CNI thresholds were applied for both LGGs and HGGs to achieve resection. The results indicated that 3D 1H-MRS can be integrated with structural imaging to provide better outcomes for glioma resection.

The bearing capacities of one-way reinforced concrete beams with elastic supports are investigated in this paper. According to the nonlinear characteristics of the beams, the basic equations based on plastic theory of concrete are derived by considering the in-plane force effects that aroused by the constraints of supports when the beams deforming. It is indicated that the calculation results are in good agreement with experimental datum, and the influences of different supports on the bearing capacities of the beams are quantitatively given for the first time.

Purpose: To isolate and characterize primary fetus retinal microvascular endothelial cells (RMECs) in order to facilitate the study of their properties in vitro. Methods: Human RMECs were isolated from abortive fetuses whose gestational ages were between 20 and 28 weeks by mechanical morcel and trypsin-collagenase digestion, plated on fibronectin-coated wells and purified gradually in high-selective condition. The RMECs were characterized for expression and localization of endothelial cell markers by indirect immunocytochemical staining of von Willebrand factor (vWF) and CD34, the distribution of cell markers was observed by confocal immunofluorescence microscope. The ability of these cells to form capillary-like networks was assessed subsequently. Cobalt dichloride (CoCl2) was used to simulate hypoxia in the culture condition and Western blot was used to detect the alternation of VEGF protein level under normoxia and hypoxia. Results: Isolation of fetus RMECs has been very difficult and primary culture of these special premature RMECs has not been previously reported due to many reasons. Here we established a simple and convenient method for the primary culture of fetus human RMECs. Our results show that delicate RMECs could be obtained readily and grow very fast, and the purity of RMECs was up to 95% demonstrated by specific staining for vWF in the cytoplasm. Our research also indicates that nearly 100% of cells could express CD34. The cells were successfully passaged and maintained in culture for 5–7 passages without a significant loss in expression of endothelia cell markers. The fetus RMECs formed capillary-like networks on the Matrigel well. Expression of VEGF protein increased significantly under hypoxia. Conclusions: Pure fetus RMECs could be obtained rapidly and easily by our method.Fetus RMECs have some specific properties. Hypoxia could induce expression of VEGF. Cell properties related with age of the donors should be considered while studying in vitro, especially in some age-specific diseases such as retinopathy of prematurity and diabetic retinopathy.

Modern electrical devices prepare less space for antennas. Both the miniaturization of antenna elements and decoupling of antenna arrays have become significant problems to solve. This paper firstly discusses the usage of lossless passive network to decouple strongly coupled antennas, such as some previous works done by other authors. Then this paper mainly concentrates on the Eigen mode decoupling theory and finds that the radiation efficiency is affected by the decoupled network because it changes the Rayleigh quotient of the whole network. Furthermore, this paper uses microstrip branch-line directional coupler to decouple two strongly couples dipoles. It comes out an isolation below −25dB at a center frequency of 3.25GHz. The passive decouple network's effect to the two-element array's radiation efficiency is analyzed in detail. And it turns out to a conclusion that the function of the decoupled network can increase the radiation ability of the whole structure.

A novel focusing lens conical horn antenna loaded with dielectric is designed in this paper. The design method of the dielectric surface equation is given. The comparison between the proposed antenna and traditional spot focusing lens antenna is well discussed. Simulations show that the proposed antenna has advantages of small reflection, low cross-polarization, symmetrical beam, and small focal spot. The antenna can be obtained very symmetrical focal spot. What's more, the focal spot is approximately circular. The average electric field strength at the focal point of the antenna can be improved by about 1/dBVm than traditional spot focusing lens antenna. This article provides a new focusing lens antenna design ideas, with good reference value.

Evidence suggests that smoking adversely affects bones. Glutathione S-transferases (GSTs) are important in the detoxification of tobacco smoke compounds. This study investigated the influence of GSTM1 and GSTT1 genetic polymorphisms on the effects on bone induced by tobacco smoking in young men. In total, 231 Chinese men aged 20-39 years were assessed by a cross-sectional study. Calcaneal quantitative ultrasound (QUS) was measured. Smoking information was obtained using a questionnaire. Genotypes were determined for null alleles of GSTM1 and GSTT1. Smoking was inversely associated with speed of sound (SOS) and bone quality index (BQI) among subjects with GSTM1 null genotype (β = -0.28, 95% CI, -34.01 to -8.65 and β = -0.30, 95% CI, -16.41 to -4.49, respectively), but not among those with the allele present (β = -0.02, 95% CI, -15.01 to 12.59 and β = -0.09, 95% CI, -8.75 to 3.02, respectively). P for interaction = 0.04 for SOS and 0.08 for BQI. No interaction was found between the GSTT1 polymorphism and smoking. The results showed that GSTM1 deficiency may increase the adverse effect of smoking on calcaneal QUS in young men, suggesting an interaction between metabolic genes and tobacco smoke in bone detoxification.

The real estate industry is one of important pillar industries of our national economy. The real estate industry is also a fund intensity industry, and it is closely related to the financial system.. Fluctuations, as a property of the real estate economy, are bound to make an impact on the financial system, leading to great financial risks, and even to a financial crisis, if not under proper control or management. This paper probes into the cause and reasons for financial risks based on the analysis on loan risks involved in real estate development and mortgage risks related to housing purchase; this thesis also makes suggestions regarding policies whose purpose is to prevent financial risks.

In the second half of 1988 the new Department of Industrial Policy of the State Planning Commission drafted ‘the first systematic industrial policy of [PRC] ‘. In March 1989 the policy was promulgated in ‘The Resolution of the State Council on Current Industrial Policy’. The policy promotes a range of industrial sectors crucial to China’s sustained economic development and international competitiveness. They include the machinery and electronic industry, especially high-value-added machine and electronic products; high-technology industries, particularly space and aviation, new materials, and biological engineering industries; high-foreign-currency-earning export sectors; infrastructure, including transportation and telecommunications; and basic industries, such as energy, steel, and chemical industries. At the same time, a range of industrial sectors will be limited. These include those machine-building industries with low-end technology and those over-developed light and processing industries in textiles, plastics, watches, and some ‘new’ consumer industries like washing machines and vacuum cleaners (Zhang 1992: p. 21).