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In this work, a method that integrates deep learning and genetic algorithms is proposed to enhance the precision and efficiency of welding robots and achieve optimal robot path planning. The process involves using SolidWorks to create a 3D model, applying the D-H method to obtain data on the connecting rod parameters, performing theoretical calculations for both forward and inverse kinematics solutions, and utilizing the MATLAB robotics toolbox to validate these solutions. Furthermore, joint space trajectory planning is performed using the quintic polynomial curve method. Through analysis, we identified that abrupt acceleration changes at the initial and final positions significantly impact the smoothness of the motion process. The findings reveal that traditional artificial bee colonies tend to stabilize after 190 iterations, whereas genetic algorithms stabilize around 160 iterations, demonstrating superior convergence speed compared to the traditional ABC algorithm. The optimized approach yields an optimal welding obstacle avoidance path with rapid optimization speed and a stable process. The proposed method effectively addresses the obstacle avoidance path planning challenge for welding robots, showcasing improved convergence speed and stability compared to traditional methods.

Underwater robot has been widely used to carry out a variety of underwater inspection and maintenance operations instead of human beings, in which the adsorption structure is an important unit for the robot to face all kinds of complex slope and elevation, so its reliability is very important. But the existing adsorption structure still has some shortcomings such as weak adsorption, poor adaptability and so on. In order to solve these problems, an adsorption structure of underwater robot based on surface negative pressure adsorption is proposed in this paper. The characteristics of the adsorption structure are analyzed through theoretical research, the adsorption structure is simulated by Ansys finite element simulation, and the effects of key parameters on the adsorption force are analyzed and discussed in detail. The theoretical calculation and simulation results show that the adsorption force produced by the adsorption structure is higher than that produced by the thruster and the plane adsorption structure. When the gap between the adsorption structure and the wall is 8 mm, the maximum adsorption force of the plane adsorption structure can reach 136 N, and the curved surface adsorption structure can produce the adsorption force of 194 N, which is equivalent to more than 4.5 times the thrust of the thruster under the same condition. The physical verification and the application verification of the underwater robot are carried out, and the creeping experiments of the robot are carried out on the vertical wall. The results show that the adsorption structure can further improve the adsorption force and contribute to the climbing and adsorption movement of the underwater robot.

The full face electric control drill rod adding device and control system are designed. The mechanical arm device of the device realizes the automatic conveying and auxiliary makeup functions of drill pipe, and solves the safety problems during manual pipe adding and auxiliary makeup; the drill pipe silo of the device has the functions of drill pipe storage, queue movement and convenient rod patching, which solves the problems of frequent manual handling of drill pipes, high labor intensity and low safety; the anti misoperation logic control loop of the device control system eliminates the mechanical collision problem that may be caused by misoperation; the single condition pressure limiting circuit of the device control system solves the problem that the maximum demand load depends on experience when making up is difficult to judge; the electric control of the device control system not only realizes the sequence logic control of the whole process of the rod adding, but also realizes the interlocking of the rod adding and drilling action, further improves the safety of the electric control operation. The full section electric control drill pipe adding device can realize the functions of one key pipe adding and automatic makeup, and it is convenient to fill the drill pipe. Compared with the manual installation of drill pipe, the efficiency is improved, the safety is significantly improved, the labor intensity of workers is significantly reduced, and the hidden danger of wrong operation is eliminated.

Underwater robot has been widely used to carry out a variety of underwater inspection and maintenance operations instead of human beings, in which the adsorption structure is an important unit for the robot to face all kinds of complex slope and elevation, so its reliability is very important. But the existing adsorption structure still has some shortcomings such as weak adsorption, poor adaptability and so on. In order to solve these problems, an adsorption structure of underwater robot based on surface negative pressure adsorption is proposed in this paper. The characteristics of the adsorption structure are analyzed through theoretical research, and the adsorption structure is simulated by Ansys finite element simulation, and the effects of key parameters on the adsorption force are analyzed and discussed in detail. The theoretical calculation and simulation results show that the adsorption force produced by the adsorption structure is higher than that produced by the thruster and the plane adsorption structure. When the gap between the adsorption structure and the wall is 8mm, the maximum adsorption force of the plane adsorption structure can reach 136 N, and the curved surface adsorption structure can produce the adsorption force of 194 N, which is equivalent to more than 4.5 times the thrust of the thruster under the same condition. The physical verification and the application verification of the underwater robot are carried out, and the creeping experiments of the robot are carried out on the vertical wall. The results show that the adsorption structure can further improve the adsorption force and contribute to the climbing and adsorption movement of the underwater robot.

Objective To summarise the process of conversion of epidural labour analgesia to anaesthesia for caesarean delivery and explore the relationship between duration of labour analgesia and conversion.Methods Parturients who underwent conversion from epidural labour analgesia to anaesthesia for caesarean delivery between May 2019 and April 2020 at the Chengdu Women’s and Children’s Central Hospital, Sichuan Maternal and Child Health Hospital, and Jinjiang District Maternal and Child Health Hospital were selected. If the position of the epidural catheter was correct and the effect was good, patients were converted to epidural surgical anaesthesia. If epidural labour analgesia was ineffective, spinal anaesthesia (SA) was administered immediately. For category-1 emergency caesarean sections, general anaesthesia (GA) was administered.Results A total of 1084 parturients underwent conversion. Of these, 19 (1.9%) received GA due to the initiation of category-1 emergency caesarean section. 704 (64.9%) were converted to epidural surgical anaesthesia, 2 (0.2%) had failed conversions and were administered GA before delivery, and 357 (32.9%) were converted to SA. Logistic regression analysis showed that prolonged duration of epidural labour analgesia ([Crude odds ratio (OR)=1.065; 95% confidence interval (CI), 1.037–1.094; p 8 h is associated with conversion failure.If it is impossible to judge whether the conversion is successful immediately, spinal anaesthesia should be administered to minimise complications.

This study reports two cases of squamous cell carcinoma of the thyroid (SCCT) presenting as the thyroid goiter, involving one case of primary squamous cell carcinoma originating from the thyroid (PSCCT) and the other case of secondary SCCT of the thyroid. A retrospective analysis of the clinical and pathological findings was done in this study report. In case 1, the thyroid ultrasound showed multi-hypoechoic well-defined nodules, labeled as 3 using Thyroid Imaging Reporting and Data System, measuring 34.1 mm × 28.9 mm × 30.3 mm and 26.5 mm × 22.2 mm × 23.9 mm in the left in the right lobar thyroid, respectively. The patient underwent surgery and was histologically diagnosed with PSCCT. In case 2, the thyroid ultrasound showed a 25.2 mm × 22.2 mm × 18.8 mm hypoechoic nodule in the right lobar thyroid. The patient underwent a frozen biopsy, the results of which increased suspicion of squamous cell carcinoma. A frozen biopsy was followed by an endoscopic evaluation that detected an ulcerative mass measuring 3.0 cm within the mucosa of esophagus. Due to a scarcity of cases, SCCT is a great challenge for the pathologists and the managing team to come up with the best treatment strategy for the patients.

In order to meet the high requirements of future high-speed and high acceleration tactical missiles for shell bearing capacity and heat protection function, the integrated structure-heat protection ϕ480 mm composite shell was prepared by dry winding process, in which the structure layer adopted T700 carbon fiber/cyanate ester composite, and the heat protection layer adopted composite heat protection structure. The internal pressure, acoustic emission and hydraulic burst tests had been done for integrated structure-heat protection ϕ480 mm shell. The strain variation law, the damage type and damage location of ϕ480 mm composite shell were researched. The structural integrity of external heat protection materials was evaluated. The capacity of bearing internal pressure load was also assessed for the integrated structure-heat protection ϕ480 mm composite shell. The results show that the strain of ϕ480 mm composite shell is linear with the pressure and increased with the raising pressure. The acoustic emission signals, such as resin cracking, monofilament fracture, fiber bundle fracture and delamination are distributed in the dome areas under the internal pressure. The Felicity ratio of ϕ480 mm composite shell is 0.96 after secondary loading. The bursting pressure of ϕ480 mm composite shell is 18.6 MPa, and the vessel characteristic coefficient reaches 42.1 km. The fiber fracture occurs in the dome areas. A small amount of fiber fuzzing, broken wire and whitening appear on the surface of the heat resistant layer material, and no delamination and shedding occur, maintaining good structural integrity.

Currently, the product quality of China’s manufacturing industry is uneven and has a notable gap with that of developed countries. Improving the quality of manufactured products is vital for upgrading China’s manufacturing industry and promoting the core competitiveness of the industry. In this study, we first analyze the development characteristics regarding the quality of the manufacturing industry, and then examine the development trend and prominent problems regarding the product quality of China’s manufacturing industry. While summarizing international experiences, we propose several suggestions for product quality improvement. Specifically, China should (1) clarify the strategic positioning of product quality development and strengthen the coherence of national quality policies; (2) focus on the needs of future industrial development by implementing three action plans; (3) accelerate the innovation of quality management theories, technologies, and tools under the guidance of digital transformation; (4) integrate the industrial quality infrastructure to support the product quality improvement; (5) reconstruct the quality development environment to promote enterprises’ willingness in improving product quality; and (6) maximize the institutional advantages of the country to implement foundation projects for improving product quality.

In view of the large output of wind power during the load trough time, the peak regulation cost may increase sharply, and the traditional hourly dispatch may not be able to accurately track the load fluctuation due to the fluctuation of renewable energy. In this paper, based on different time granularities, an adaptive segmented double-layer economic scheduling model of the net load curve considering reasonable wind abandonment is constructed. The model can better cope with net load changes while reducing the load peak-to-valley difference. First, a reasonable wind abandonment model is established under different time granularities of 5 min, 15 min, 30 min, and 1 h; Then, based on the static thinking of the net load curve by time period, the load change in the hourly scale is fully considered without changing the total number of dispatching periods so that each dispatching period can adaptively select the duration according to the change of net load gradient, and a self-adaptive subsection model of the net load curve is established to minimize the total running cost. Finally, taking IEEE-30 nodes as the example system, the NSGA-II algorithm and CPLEX solver are used to solve the model. The results verify the economy and feasibility of the proposed model.

Objective To investigate the correlation between BRAFV600E and different clinical features of Papillary Thyroid Carcinoma (PTC). Methods The clinical and pathological data of 164 patients diagnosed with PTC between December 2016 to December 2019 in Baoding First Central Hospital were selected, detecting the BRAFV600E gene mutation in patients and analyzing the correlation between BRAFV600E mutation rate and different clinicopathological characteristics in order to investigate the effect of BRAFV600E mutation on clinicopathological characteristics and prognosis of PTC patients. Results A total of 164 PTC patients were included, 52 (31.7%) patients had papillary thyroid carcinoma combined with Hashimoto's thyroiditis, 132 (80.5%) patients developed cervical lymph node metastasis, 48 (29.3%) patients were≥55 years old, and 108 (65.9%) patients were detected BRAFV600E mutation. Hashimoto's thyroiditis was associated with the age, lesion location, maximum tumor diameter and nodular calcification in PTC patients (P

Objective To investigate the association between RET genotype and disease phenotype in the patients with hereditary medullary thyroid carcinoma (HMTC). Methods A total of 13 patients diagnosed as HMTC and undergoing surgical treatment for thyroid carcinoma in this hospital from March 2015 to September 2019 were analyzed retrospectively with follow-up cutoff at September 2021. The patient risk stratification was performed according to American Thyroid Association (ATA) guidelines. The association between RET genotype and disease phenotype including biochemical results, TNM stage, both biochemical [normal serum calcitonin(CT)] cure and clinical cure was analyzed. Results There were 1 (7.69%) case, 6(46.15%) cases, and 6(46.15%) cases with the highest risk mutation (RET M918T), high-risk mutation (RET C634Y and C634S), and moderate-risk mutation (RET C618G and C611Y), respectively. One case with the highest risk mutation was at TNM stage Ⅳ. There were 4 cases (66.67%) at stageⅠand 2 cases (33.33%) at stage Ⅲ among 6 cases with high-risk mutation. For 6 cases with moderate-risk mutation, stage Ⅰ and stage Ⅱ had 1 case(16.67%) respectively, and stage Ⅲ and stage Ⅳ with 3 cases (50%) and 1 case (16.67%) respectively. The highest preoperative CT and carcinoembryonic antigen were detected in 1 case with highest risk mutations (20 000 ng/L, 831.8 μg/L), and those lower in 6 cases with moderate-risk mutations (1 221.4 ng/L, 62.3 μg/L). The lowest of them were in 6 cases with high-risk mutations (537.7 ng/L, 41.7 μg/L). Similarly, both clinical cure rate and biochemical cure rate were found poorer in the cases with the highest risk mutation, and better in the case with high-risk mutation, and less better in the cases with moderate-risk mutation. Conclusions RET gene could be associated with HMTC risk of ATA. The patients of RET genotype with high-risk mutations would have higher clinical cure rate and biochemical cure rate than the cases with moderate-risk mutations.

BackgroundChina Spallation Neutron Source (CSNS) based on the spallation reaction is a large multidisciplinary research facility, which has been constructed and commissioned since August 2018. Experimental Muon Source (EMuS) is one of the important research platforms for the future construction of CSNS. The proton beam energy is 1.6 GeV and the power on the carbon target is 20 kW.PurposeThis study aim to design radiation and shielding system for EMuS that satisfies the requirements of radiation safety.MethodsThe Monte Carlo simulator of FLUKA was used to calculate and analyze the prompt radiation and residual radiation. According to the dose limit, the shielding optimization design was carried out, and abandoned proton beam flux was estimated. Finally, computational results of FLUKA were analyzed, and compared with that of the Moyer mode semi-empirical formula.ResultsThe simulation results show that the exterior residual radiations of shielding for the high radiation area such as target area, collimation area, dump and muon transport line are very low whilst the inside components such as carbon target, magnets, and vacuum pipes of high-energy proton transport line are critically activated and have high residual radiation. The abandoned proton beam after carbon target is of 1012 cm-2∙s-1.ConclusionsThe optimal shielding design meets the requirements of prompt radiation protection for EMuS of CSNS, but the strategy of remote operations and strict control of maintenance time need to consider for the future maintenance and upgrade. Abandoned proton beam can be efficiently utilized to build a proton irradiation platform and a neutron irradiation platform with carefully studying of the background of those irradiation points.

It is often difficult to quickly troubleshoot and repair the complex electro-hydraulic control system of remote control drilling rigs. Therefore, it is proposed to establish its electro-hydraulic control system monitoring system to quickly find the fault point. Based on the analysis of the fault characteristics of typical load-sensitive electro-hydraulic control systems, the method of real-time monitoring of the inlet and outlet pressure and flow of key hydraulic components is adopted, and the method of periodic monitoring of the communication, control and accuracy of the electronic control components is compared in the controller. The fault status of components is determined and monitored to improve the overall construction efficiency of remote drilling rigs.

Objective To investigate the expression of mediator complex subunit 28 protein (MED28) in oral squamous cell carcinoma (OSCC) and para-carcinoma tissues, and its correlation with pathological features and prognosis. Methods A total of 142 OSCC specimens were collected from the inpatients undergoing surgical treatment in our department from January 2015 to June 2020. Among these specimens, 91 had para-carcinoma tissues. Immunohistochemistry was used to detect the MED28 expression in OSCC and para-carcinoma paraffin sections. Chi-square test was used to analyze the difference of MED28 expression between OSCC and para-carcinoma tissues. The patients were then divided into MED28-high and MED28-low expression groups according to its median expression level. Logistic regression model was used to analyze the relationship between MED28 expression and pathological features, Kaplan-Meier survival analysis was selected to study the relationship between the expression and prognosis, and COX regression analysis was employed to analyze the prognostic factors. Results MED28 was significantly highly expressed in the OSCC tissues than para-carcinoma tissues (P < 0.01). Logistic regression model showed that MED28 expression is related with smoking and lymph node metastasis(P < 0.05). Kaplan-Meier survival analysis indicated that overall survival (OS) in the patients was significantly higher in the MED28-low expression group than the MED28-high expression group (P < 0.01). Gender and smoking status were identified as related factors influencing prognosis (P < 0.05). Conclusion MED28 is highly expressed in the OSCC tissues, which might be related to the occurrence and development of OSCC. It also affects the prognosis, and is related to smoking status and lymph node metastasis.

Objective To establish a smoothed particle hydrodynamics (SPH) model for simulating the process and biomechanical characteristics of blast injuries in human mandible. Methods Based on computed tomography and magnetic resonance imaging (MRI) data of the maxillofacial region in human, we established a SPH model of blast injuries in the mandible and masseter muscles and assessed its validity by comparison with a three-dimensional finite element model (FEM). Result The number of particles in the SPH model of mandible is 4 538, which is similar to anatomical structure of human, with less loss of details. The SPH model simulates the explosion damage of mandible and masseter caused by blast wave. The explosion results in the fractures in the left mandibular angle and condyle, and extensively torn in the masseter muscle is. The simulation results are close to the FEM. Conclusion Compared with the FEM model, the SPH model shows obvious advantages in simulating large tissue deformation, crack growth and explosion impact on the mandible, and provides a new method for studying maxillofacial blast injuries.

Objective To establish a risk regression model based on proliferation-related genes in oral squamous cell carcinoma (OSCC) for evaluating the prognosis of patients with OSCC. Methods We retrieved 1 899 proliferation-related genes from the Molecular Signatures Database (MSigDB) and down-loaded from Cancer Genome Atlas (TCGA) the gene expression and clinical data of OSCC patients, who were randomly divided into the training group and validation group at the ratio of 7:3. The proliferation-associated differentially expressed genes (PADEGs) between OSCC and adjacent tissues were identified by Wilcoxon test. The proliferation-related gene risk regression model was constructed by single factor Cox analysis and Lasso regression analysis, and the accuracy of the model was evaluated through survival analysis and independent prognosis analysis. The constructed model was further verified using the data of OSCC patients in the validation group. Results Eight genes (APP, STC1, SFRP1, ABCB1, HPRT1, ZAP70, ST8SIA1, and ADGRG1) were screened for construction of the risk regression model. The OSCC patients with high risk scores calculated with the constructed model had significantly poorer prognosis (P < 0.01). The score of the risk regression model based on the proliferation-related genes was an independent prognostic factor in OSCC patients (P < 0.01). Conclusion The proliferation-related gene risk regression model provides a reliable means for evaluating the prognosis of OSCC patients to facilitate clinical interventions and management of the patients

Objective To analyze the biomechanical response of temporomandibular joint (TMJ) musculoskeletal system under lateral impact load through 3D finite element method (FEM). Methods The finite element model of TMJ system was built based on the combination of CT and MRI data of human head by finite element software. The Von Mises stress cloud maps of TMJ structures and the dynamic maps of mandibular fractures were obtained by the impact of impactor was simulated on the mandibular angle. Results The peak stress was found in the impacted condyle neck area. When the impacting velocity was at 2.87 m/s, there was no fracture; as the velocity increased to 7.22 m/s, the left condyle just happened to have a linear fracture without displacement; the left condyle completely fractured as the speed at 8.33 m/s; when the velocity was 9.72 m/s, then both 2 condyles and the mental region completely fractured. The high stress in the condyle neck was transmitted to the articular fossa, which was rapidly reduced by the cushioning effect of the articular disc. Under the impact condition of this experiment, the joint disc and the masseter muscle were compressed and deformed under the stress. Conclusion With the aid of FEM, the injury process of TMJ under the impact load of different velocities on the angle of mandibular simulate is stimulated. The model can quickly and accurately predict the injury types of TMJ structures and guide clinical protection.

Pingwu County, which is located at the northern end of the Longmenshan fault structural belt, has an active regional geological structure. For a long time, the Longmenshan fault tectonic belt has become intensely active with frequent earthquakes. According to the existing geological data, the Pingwu–Qingchuan fault passes through the urban area of Pingwu. However, because of the great changes in the original landform of Pingwu caused by the construction activities in this urban area, a precise judgment of the location of the Pingwu–Qingchuan fault according to the new landform characteristics is difficult. Here, the seismic reflection method, electrical resistivity tomography (ERT), and drilling method were used to determine the accurate location of the buried active faults in Pingwu County. The seismic reflection method and ERT are used to determine the location of faults, the thickness of overlying strata of the fault, and the basic characteristics of faults. The drilling data can be used to divide the bedrock lithology and confirm the geophysical results. The geological model of the faults can be constructed by 3D inversion of ERT, and the structural characteristics of the faults can be viewed intuitively. The results of this study can provide a basis for earthquake prevention and construction work in Pingwu. The finding also shows that seismic reflection method and ERT can effectively explore buried active faults in urban areas, where many sources of interferences may exist.

Objective To explore the law of the change of human heart rate under plateau environmental exercise load and establish an evaluation method of optimal labor intensity at plateau. Methods Sub-polar treadmill exercise test was used to measure the exercise heart rate and recovery heart rate of 228 subjects under different exercise load conditions at plain (altitude 300 m) and plateau (altitude 3 700, 4 200, 4 600 and 5 100 m). The maximum oxygen consumption (VO2max), heart rate change amplitude (X) and relative heart rate comprehensive index (Z) were calculated. Results Compared with the plain, VO2max of subjects from 3 700 m to 5 100 m at high altitude was decreased significantly (41.74±2.96, 41.25±2.84, 41.08±2.35, 41.60±2.82 vs 46.61±3.74 mL·kg-1·min-1, P < 0.05). The Z value of the relative heart rate comprehensive index was increases linearly with the increase of the X value of the heart rate change amplitude (Z=0.920+0.006X, R2=0.794). The Z value of moderate labor intensity (1.42±0.21) was obviously lower than that of severe labor intensity (1.52±0.23, P < 0.05). Conclusion Plateau environment significantly decreases the labor capacity of human body. So, the suitable labor intensity at plateau should be within the range of moderate labor intensity. Z=1.42 can be used as the cut-off value for judging moderate labor intensity in plateau environment.

Background: In recent years, the incidence of thyroid cancer is on the rise, almost become one of the fastest-growing malignant tumor, especially in women. The reasons of the incidence of thyroid, is not only the use of detection means. The relationship between clinical pathological characteristics and prognosis of thyroid is controversial. Aims and Objective: One thousand forty seven cases of thyroid nodule (thyroid nodules, TN) were retrospectively analyzed, to study the distribution of TN and its clinical pathological features. Materials and Methods: Clinicopathological data of 1047 cases TN were retrospectively studied, from Chengde Medical College Affiliated Hospital and (10.2017 to 08.2018) Chengde County Hospital (01. 2016 to 08.2018), χ2 test is used to analyze the relationship between clinical pathologic factors and lymph node. Results: In 1047 cases of TN, nodular goiter 50.62%, Hashimo-to’s thyroiditis 3.34%, thyroid carcinomas 32.28%,thyroid adenoma 10.12%, toxic nodular goiter 0.29%. The lymph node metastasis positive rate was higher in 1 cm of the thyroid carcinoma patients. Gender, whether single had no relation with occurrence of neck lymph node metastasis. Conclusion: The lymph node metastasis positive rate is higher in

Through theoretical derivation and finite element simulation, the vibration characteristics of composite laminate with four-edge clamped support under hygrothermal condition were studied. Based on the Mindlin first-order shear deformation theory and the Hamilton principle, taking the effect of hygrothermal stress into account and using the equivalence of temperature and humidity, the constitutive equation of composite laminate affected by the hygrothermal environment was derived. The finite element method was used to solve the vibration characteristic equation of the laminate. Bonding repaired laminate model was established by using the finite element software ABAQUS, and the model was compared with literature results. The effects of different hygrothermal environments and the number of additional patches on the vibration characteristic of the bonding repaired laminate were discussed. The results of the example show that in the hygrothermal environment, the introduction of additional patch reduces the natural frequencies of the various orders of the bonding repaired laminate. When the number of additional patches changes from one to two, the first-order natural frequency decreases further. The effect of increased humidity on natural frequency reduction is greater than that of temperature increase on natural frequency. In the environment where the temperature and humidity are simultaneously increased, the introduction of the additional patch will cause the bonding repaired laminate to reach the state of hygrothermal buckling earlier.

Recently, layered two-dimensional (2D) palladium diselenide (PdSe2), with a unique low- symmetry puckered pentagon atomic morphology, has emerged as a promising candidate for next-generation nanoelectronics and optoelectronics because of its chemical stability and extraordinary electrical properties. Moreover, PdSe2 possesses a strong thickness-dependent bandgap that varies from 0 eV for bulk to 1.3 eV for monolayer, which can further render its potential applications in optoelectronics. However, the layer-dependent optoelectronic properties of PdSe2 are still lacking up to date. Herein, we studied the optoelectronics transport characteristics of high-quality PdSe2-based photodetectors with different thicknesses. We demonstrated an enhancement of PdSe2 photodetector performance owing to the band engineering via a thickness reduction. The highest responsivity of 5.35 A/W can be achieved with an external quantum efficiency of 1250% at the wavelength of 532 nm. We attribute such high performance in photoresponsivity to the high valley convergence in the conduction band of layered PdSe2, in agreement with first-principles calculation. Our results offer new insight into the layer-dependent optoelectronic properties of PdSe2 and open new avenues in engineering next-generation 2D-based electronics and optoelectronics.

Objective To explore the effect of the periodontal systematic therapy on chronic periodontitis. Methods One hundred patients with chronic periodontitis admitted in our department from January to December 2017 were recruited in this study. All the patients accepted periodontal systematic therapy, including periodontal initial therapy, periodontal surgical therapy, and periodontal supportive therapy. Clinical parameters, such as probing depth (PD), clinical attachment level (CAL), tooth mobility (TM) and bleeding on probing (BOP) were recorded by Florida electronic probe before and at 1 to 6 months after therapy. Statistical analysis was carried out. Results At 6 months after treatment, BOP, CAL and PD were significantly decreased, the positive sites of BOP were obviously reduced, and TM was greatly improved (P < 0.05). There were no statistical differences in the above indicators at 1, 3 and 6 months after therapy. Conclusion Periodontal systematic therapy is effective and stable for chronic periodontitis

C24H36CoMo4N12O13, triclinic, P1̄ (no. 2), a = 11.155(5) Å, b = 13.889(6) Å, c = 14.081(6) Å, α = 64.544(12)°, β = 79.558(14)°, γ = 87.084(14)°, V = 1936.3(15) Å3, Z = 2, Rgt(F) = 0.0365, wRref(F2) = 0.1171, T = 293(2) K.

Graphene, as a rising star in materials science, is intensively studied in Li-ion batteries and supercapacitors, owing to its unique structure and excellent properties. The research status of the application of graphene in energy storage field was disscussed and the future development trend was predicted, and therefore to enhance the understanding of the structure-performance relationship of graphene and also the application of graphene in this field. Firstly, the application of graphene in cathode and anode of Li-ion battery, and the application of graphene in electrical double-layer capacitor and pseudo-capacitor were introduced. Secondly, the challenges of graphene in electrical double-layer capacitor were discussed and the ideal structure of graphene applied to electrical double-layer capacitor was proposed. Finally, the "three steps" to realize the commercial application of graphene-based electrical double-layer capacitor were put forward.

In order to meet the demand of surfing Internet of users when traveling abroad, a virtual SIM card is designed and implemented based on Android smart phone. It allows the user download information of the virtual SIM through the terminal in the destination area. After an authentication with the download card parameters, it can also provide data network service with the price similar to the destination area by accessing to the Internet. Firstly, the Android Telephony architecture is introduced, and then the method of communication interaction of each layer is analyzed. For security issues that may arise from the virtual card, this article achieves the security management of virtual card parameters based on ARM TrustZone technology. Experimental results show that users could achieve the order to products and the activation to orders by the application. By using the virtual SIM card, users can enjoy the Internet service in which the cost is lower than operators.

Sparse coding is currently an active topic in signal processing and pattern recognition. Meta Face Learning (MFL) isatypical sparse coding method and exhibits promising performance for classification. Unfortunately, due to using the l1-norm minimization, MFLis expensive to compute and is not robust enough. To address these issues, this paper proposesafaster and more robust version of MFLwith the l2-norm regularization constraint on coding coefficients. The proposed method is used to learnaclass-specific dictionary for facial expression recognition. Extensive experiments on two popular facial expression databases, i.e., the JAFFEdatabase and the Cohn-Kanade database, demonstrate that our method shows promising computational efficiency and robustness on facial expression recognition tasks.