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We proposed a high-performance integrated optical sensor based on a stacked resonant compound grating (SRCG). The transmission spectrum of a SRCG is investigated by the theoretical model that combines the coupled mode theory with the eigenmode information of the grating structures. It is found that the spectral width of the SRCG is controlled by changing its structural parameters such as the strip depth, the period of the grating, and cavity length. The simulation results, which are verified by finite element method (FEM), show that the sensitivity of the sensor is 401.8 nm/RIU with its figure of merit (FOM) as high as 57404. The presented sensor is a promising application for high-performance biosensing.

A structure with new meta-atom is proposed. The meta-atom with C3 rotational symmetry consists of three slits. The slits are drilled in the metal. Based on this meta-atom, metasurface lenses with different functions are designed. It is based on the phase and amplitude modulation by tuning the rotational angle of the meta-atom. The rotational angle of each meta-atom is achieved by simulated annealing algorithm. Three kinds of focal lenses, which can realize one or two focus points on the left and right sides, have been designed in terahertz frequency. The finite-difference time-domain method is employed to verify and appraise the properties of the designed lenses. Simulation results show that the designed lenses can perform the preset functions well. It demonstrates that such meta-atom is more suitable for focusing metasurface in different directions. It will promote the lightness, miniaturization and integration of optical components. And it is more suitable for microwave and terahertz wavefront modulation.

A high performance optical sensor based on a double compound symmetric gratings (DCSGs) structure is designed. The reflection spectrum of the DCSG is investigated by utilizing a method that combines a theoretical model with the eigenmode information of the grating structure. The theoretical results, which are observed to agree well with those acquired by rigorous coupled-wave analysis, show that the linewidth of the reflection spectrum decreases upon the increasing distance between the grating strips. This research work will lay a foundation for studying high performance integrated optical sensors in miniature nanostructures.

Background/Aims: Huangqi Decoction (HQD) has been traditionally used to treat diabetes mellitus in China. The present study was carried out to assess the protective effect of HQD on diabetic nephropathy (DN) using the streptozotocin-induced (STZ) diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg) in male Wistar rats. 40 diabetic rats were divided into 5 groups: vehicle-treated (DN group), 0.45, 0.15, 0.05 g/kg HQD-treated diabetic group (HQD group) and 1 mg/kg rosiglitazone-treated diabetic group (RGZ group). 16 normal rats were randomly divided into 2 groups: vehicle-treated normal control group (NC) and 0.45 g/kg HQD-treated normal control group (NC+0.45 g/kg HQD). At the end of 8-week experiment, we measured changes of renal pathological morphology, function, antioxidant enzyme levels and the activation of TGF-β/PPAR-γ/MAPK signaling pathway. Results: After HQD treatment, renal function, including blood urea nitrogen (BUN), 24-h albuminuria and blood glucose level were improved significantly; meanwhile, impaired kidney redox balance was diminished in diabetic rats. The activation of TGF-β, phospho-JNK, phospho-p44/42, p47 and p42 phox was blocked and the decrease in PPAR-γ in diabetic rats was attenuated by treatment with HQD in a dose-dependent manner. Conclusion: These results suggest that HQD shows therapeutic efficacy in DN characterized by renal dysfunction and pathological changes through hypoglycemic and antioxidant effects.

In order to investigate the sleep quality and influencing factors in patients with Parkinson's disease (PD), 201 PD patients were enrolled and underwent extensive clinical evaluations. Subjective sleep evaluation was assessed using the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). It was found that poor sleep quality (77.11%) and excessive daytime sleepiness (32.34%) were commonly seen in PD patients and positively correlated with disease severity. Then 70 out of the 201 PD patients and 70 age- and sex-matched controls underwent a polysomnographic recording. The parameters were compared between PD group and control group and the influencing factors of sleep in PD patients were analyzed. The results showed that sleep efficiency (SE) was significantly decreased (P

A numerical model for analyzing airtraintrack interaction is proposed to investigate the dynamic behavior of a high-speed train running on a track in crosswinds. The model is composed of a traintrack interaction model and a trainair interaction model. The traintrack interaction model is built on the basis of the vehicletrack coupled dynamics theory. The trainair interaction model is developed based on the train aerodynamics, in which the Arbitrary LagrangianEulerian (ALE) method is employed to deal with the dynamic boundary between the train and the air. Based on the airtraintrack model, characteristics of flow structure around a high-speed train are described and the dynamic behavior of the high-speed train running on track in crosswinds is investigated. Results show that the dynamic indices of the head car are larger than those of other cars in crosswinds. From the viewpoint of dynamic safety evaluation, the running safety of the train in crosswinds is basically controlled by the head car. Compared with the generally used assessment indices of running safety such as the derailment coefficient and the wheel-load reduction ratio, the overturning coefficient will overestimate the running safety of a train on a track under crosswind condition. It is suggested to use the wheel-load reduction ratio and the lateral wheelrail force as the dominant safety assessment indices when high-speed trains run in crosswinds.

For the problem of multiaircraft cooperative suppression interference array (MACSIA) against the enemy air defense radar network in electronic warfare mission planning, firstly, the concept of route planning security zone is proposed and the solution to get the minimum width of security zone based on mathematical morphology is put forward. Secondly, the minimum width of security zone and the sum of the distance between each jamming aircraft and the center of radar network are regarded as objective function, and the multiobjective optimization model of MACSIA is built, and then an improved multiobjective particle swarm optimization algorithm is used to solve the model. The decomposition mechanism is adopted and the proportional distribution is used to maintain diversity of the new found nondominated solutions. Finally, the Pareto optimal solutions are analyzed by simulation, and the optimal MACSIA schemes of each jamming aircraft suppression against the enemy air defense radar network are obtained and verify that the built multiobjective optimization model is corrected. It also shows that the improved multiobjective particle swarm optimization algorithm for solving the problem of MACSIA is feasible and effective.

Jilin province is an important agricultural production resource in our country. Study on the temporal and spatial variability of maize yield are significant to understand the potential nutrients in soil, and guide agricultural practice for the recent years in precision operate area. The every year yield distribution belonged to the normal distribution by testing K-Sand the coefficient of variation of them were 16.33%, 11.85%, 12.90% respectively. That precise operation can reduce the yield difference in every operate cell. As a result, the temporal and spatial variability of maize yield can be successfully applied to yield prediction in Jilin Province. Partition results can not only guide soil nutrient evaluation, and can be used to implement variable input and precise fertilization recommendation.

As a user modeling method, Bayesian Knowledge Tracing BKT has been extensively used in the area of Intelligent Tutoring Systems ITS. Thereafter the various schemes based on BKT are proposed to model student knowledge state and learning process. However, these schemes seldom consider the situation when a student first encounters a knowledge component KC. That is, the existing models cannot be applied directly to predict student performance on a first-encounter KC. To solve this issue, combined user-based collaborative filtering and BKT model, a novel student performance prediction scheme PSFK is proposed in this paper. The PSFK scheme contains three major steps: first, building BKT models for each student and each KC he or she has encountered; then, finding the top-k similar students for a specified student S; finally, predicting S's response on first-encounter KC. We evaluate our scheme on a real-world data set which contains 4883 students and 177 KCs. The experiments show that the student performance prediction results of the proposed PSFK are acceptable the RMSE can be decreased to 0.403.

Many real-world systems can be depicted as interdependent networks and they usually show an obvious property of asymmetry. Furthermore, node or edge failure can trigger load redistribution which leads to a cascade of failure in the whole network. In order to deeply investigate the load-induced cascading failure, firstly, an asymmetrical model of interdependent network consisting of a hierarchical weighted network and a WS small-world network is constructed. Secondly, an improved “load-capacity” model is applied for node failure and edge failure, respectively, followed by a series of simulations of cascading failure over networks in both interdependent and isolated statuses. The simulation results prove that the robustness in isolated network changes more promptly than that in the interdependent one. Network robustness is positively related to “capacity,” but negatively related to “load.” The hierarchical weight structure in the subnetwork leads to a “plateau” phenomenon in the progress of cascading failure.

It has been reported that R2* is a sensitive marker for iron deposition. The aim of this study was to quantitatively assess iron deposition in Parkinson's disease (PD) using changes of R2* in enhanced T2 star-weighted angiography (ESWAN) and to discuss the value of ESWAN for PD.Fifty-four primary PD patients and twenty-eight healthy individuals were examined by ESWAN in the 3·0 T magnetic resonance imaging system. The R2* values were measured from the deep gray nuclei (including the substantia nigra [SN], red nuclei, globus pallidus, putamina, caudate nuclei, and thalami). The unified PD rating scale (UPDRS) III assessment, the nonmotor symptoms scale (NMSS), and the mini mental state examination (MMSE) were used to rate all the patients.The comparison of the R* values between the deep gray nuclei on the same side of the PD patients and the control group revealed significant differences in the SN and red nuclei (P0.05). There was a significant difference between Hoehn and Yahr (HY) 1 and HY2-4 patients in terms of the values of the SN. There was a slight correlation between the R* values of the SN of the PD patients (HY1) and the UPDRS III ratings. No correlation between the R* signal values in the PD patients and the NMSS and MMSE scales was found.Iron concentrations in the regions of interest may represent the severity of the PD motor symptoms, and whether they are related to the nonmotor symptoms remains a question for further investigation. ESWAN offers special advantages in determining iron depositions in the brain and in enabling a sensitive diagnosis of PD, although further study is necessary.

The primary objective of this paper was to integrate two research traditions, social cognition approach and individual state approach, and to understand the relationships between locus of control (LOC), risk perception, flight time, and safety operation behavior (SOB) among Chinese airline pilots. The study sample consisted of 193 commercial airline pilots from China Southern Airlines Ltd. The results showed that internal locus of control directly affected pilot safety operation behavior. Risk perception seemed to mediate the relationship between locus of control and safety operation behaviors, and total flight time moderated internal locus of control. Thus, locus of control primarily influences safety operation behavior indirectly by affecting risk perception. The total effect of internal locus of control on safety behaviors is larger than that of external locus of control. Furthermore, the safety benefit of flight experience is more pronounced among pilots with high internal loci of control in the early and middle flight building stages. Practical implications for aviation safety and directions for future research are also discussed.

Yield in a given field may vary in space depending on a combination of factors such as nutrient availability, soil moisture, rooting depth, pest pressure and others. In order to enhance the yield of agricultural production, the maize sharing fertilizer expert system based on oracle database was developed. During designing the system, the author collected clearly some materials for the system and communicated with domain experts about knowledge of maize fertilizer. The sharing system was based B/S. Considering the characteristic of operational research, the author have designed six function modules, which have not been isolated one another, but have integrated to all modules. Every function includes some sub-function modules.