INTRODUCTION:Osteosarcoma is the most common primary malignancy of the bone among adolescents and children. Despite intensive chemotherapy and aggressive surgery, the 5-year survival rate of osteosarcoma still falls under 70%, mainly due to its tendency to metastasize and to develop drug resistance. Therefore, new treatments for osteosarcoma are urgently needed. HGF/c-Met signaling pathway, when dysregulated, is involved in the onset, progression and metastasis of various cancers, making the HGF/c-Met axis a promising therapeutic target.METHODS:In this study, we found Met to be a cancer-promoting gene in osteosarcoma as well, and aimed to investigate the role of a c-met inhibitor (PHA-665752) in osteosarcoma. For this purpose, two human osteosarcoma cell lines (143B and U2OS) were introduced in this study and treated with PHA-665752. CCK8 cell proliferation assay was performed to obtain the IC50 value of PHA-665752 for 143B and U2OS. After that, colony formation assay, transwell migration and invasion assay and wound-healing assay were performed. Furthermore, a tumor-transplanted mouse model was used for in vivo experiments.RESULTS:Our results showed that PHA-665752 could suppress osteosarcoma progression, promote apoptosis and inhibit proliferation of human osteosarcoma cells. Moreover, we found ERK1/2 pathway to be an important mediator underlying the osteosarcoma-suppressing function of PHA-665752. LY3214996, a highly selective inhibitor of the ERK1/2 pathway, was able to antagonize the effects of PHA-665752 in osteosarcoma. Finally, in vivo experiments indicated that PHA-665752 suppressed tumor growth in a tumor-transplanted mouse model.CONCLUSION:Taken together, Met provided a druggable target for osteosarcoma and PHA-665752 is a promising candidate for anti-osteosarcoma treatments.

The planning of whole-body motion and step time for bipedal locomotion is constructed as a model predictive control (MPC) problem, in which a sequence of optimization problems needs to be solved online. While directly solving these problems is extremely time-consuming, we propose a predictive gait synthesizer to offer immediate solutions. Based on the full-dimensional model, a library of gaits with different speeds and periods is first constructed offline. Then the proposed gait synthesizer generates real-time gaits at 1 kHz by synthesizing the gait library based on the online prediction of centroidal dynamics. We prove that the constructed MPC problem can ensure the uniform ultimate boundedness (UUB) of the CoM states and show that our proposed gait synthesizer can provide feasible solutions to the MPC optimization problems. Simulation and experimental results on a bipedal robot with 8 degrees of freedom (DoF) are provided to show the performance and robustness of this approach.

NiCo2O4 nanoneedles were grown on reduced graphene oxide (rGO) by a hydrothermal method. Physical characterization and electrochemical tests were performed on the composites. The NiCo2O4/rGO composites possessed a high capacitance of 1757 F g−1 (1 A g−1). The composites possessed 97.3% of initial capacity after 2500 cycles (10 A g−1). Furthermore, the prepared NiCo2O4/rGO//AC asymmetric supercapacitor obtained a well energy density of 32.38 W h kg−1. After 10000 cycles at 5 A g−1, 90.4% of the capacity was retained. Therefore, the NiCo2O4/rGO nanocomposites appear to be excellent candidates for high performance supercapacitors.

Deep learning models plays a significant role in bioinformatics research, such as prediction of incidence, classification of disease samples, identification and detection of tumor areas. Mass spectrometry (MS) has been widely applied to protein research due to its high throughput and sensitivity. Tumor protein mass spectrometry data has high sample dimensions and low signal-to-noise ratio, which is difficult to extract features for classification. Here, we aim to develop a new method to extract features from tumor protein mass spectrometry data and classify proteomics data using deep learning models. Our results demonstrated that the deep learning models we proposed has a good performance and may provide ideas for researchers to classify other protein mass spectral data or similar data.

Since the launch of Chinese Human Proteome Project (CNHPP) and Clinical Proteomic Tumor Analysis Consortium (CPTAC), large-scale mass spectrometry (MS) based proteomic profiling of different kinds of human tumor samples have provided huge amount of valuable data for both basic and clinical researchers. Accurate prediction for tumor and non-tumor samples, as well as the tumor types has become a key step for biological and medical research, such as biomarker discovery, diagnosis, and monitoring of diseases. The traditional MS-based classification strategy mainly depends on the identification and quantification results of MS data, which has some inherent limitations, such as the low identification rate of MS data. Here, a deep learning-based tumor classifier directly using MS raw data is proposed, which is independent of the identification and quantification results of MS data. The potential precursors with intensities and retention times from MS data as input is first detected and extracted. Then, a deep learning-based classifier is trained, which can accurately distinguish between the tumor and non-tumor samples. Finally, it is demonstrated the deep learning-based classifier has a good performance compared with other machine learning methods and may help researchers find the potential biomarkers which are likely to be missed by the traditional strategy.

Web service-based application has become one of the dominative ones of the Internet. This trend brings more and more security challenges in reliability, confidentiality, and data nonrepudiation, especially in some systems that have massive diversified resources. An improved framework for secure accesses of Web resources is presented and implemented by extending and enhancing the Spring Security framework. It improves the security level of systems for identity authentication, authorized access, and secure transmission. The highly safe authentication is based on the integration of an improved authentication module of Spring Security with a U-key method and a RSA algorithm. For authorized access, the Spring Security's ACL (access control list) mechanism is improved by optimizing the domain object-level access control. For secure transmission, a compromising method is presented to take both the security level and the speed of data transmission into account by means of mixing the RSA and DES algorithms. In addition, the security interceptor of Spring Security is extended and a series of security filters are added to keep Web attacks away. The above improved security framework has been applied to an online virtual experiment platform named VeePalms. The experimental results show that most security problems with high severity in the system have been solved and medium-low severe problems decreased dramatically. Moreover, VeePalms has been used in practice for about 2 years, which has proved the effectiveness of the security framework.

In this paper, we present an application of the moving mesh method for approximating numerical solutions of the two-phase flow model in porous media. The numerical schemes combine a mixed finite element method and a finite volume method, which can handle the nonlinearities of the governing equations in an efficient way. The adaptive moving grid method is then used to distribute more grid points near the sharp interfaces, which enables us to obtain accurate numerical solutions with fewer computational resources. The numerical experiments indicate that the proposed moving mesh strategy could be an effective way to approximate two-phase flows in porous media.

为拓展杨木高附加值利用途径,对皱缩严重的杨木地板坯料进行汽蒸处理.结果表明:随着处理时间的延长,皱缩杨木地板坯料的含水率增加,皱缩深度减小.经汽蒸5h处理和干燥后,试样的皱缩深度明显减小.

Web service technologies have been widely used in diverse applications. However, there are still many security challenges in reliability, confidentiality and data nonrepudiation, which are prominent especially in some Web service systems that have massive resources in diverse forms. An enhanced mechanism for secure accesses of Web resources is presented and implemented based on the combination of modules of identity authentication, authorized access, and secure transmission to improve the security level of these systems. In the identity authentication, the highly safe and recognized authentication method U-Key is used. For the aspect of authorized access, the integration of an improved Spring Security framework and J2EE architecture is applied to ensure authorized access to Web resources, while the security interceptor of Spring Security is extended and a series of security filters are added to keep web attacks away. Moreover, some improvements of the XML encryption and XML decryption algorithm are made to enhance the security and speed of data transmission, by means of mixing RSA and DES algorithm. The above security mechanism has been applied to an online virtual experiment platform based on Web services named VeePalms. The experimental results show that most security problems with high severity in the system have been solved and medium-low severe problems degreased dramatically.

Aimed at improving the disturbance rejection ability of the stable platform on the moving carrier,this paper proposes the stable control of disturbance observer with output observer by allowing for the mechanical resonant factors of stable platform servo system and describes the study of the loop structure,the input and output stability issues and the relationship between bandwidth and robustness of the disturbance observer.Simulation shows that LOS stabilization shows a precision of less than 0.04°,in the presence of the carrier moving at a maximum rate of 4（°）/s angular velocity in the case of sinusoidal signal movement with frequency of 5 Hz.Disturbance observer with output observer working,in the case of parameter perturbation,shows a better robust stability than feedback disturb observer.

A disturb dual rejection circuit was generated base on disturb observer to improve the anti-disturb performance of a electronic optical tracking servo system on a shift carrier.The circuit structure,the circuit input and output relationship and the circuit output characteristic on servo saturation were analyzed.Applied in electronic optical tracking servo system,it improved the line of sight(LOS) stabilized precision.The LOS stabilized precision reached less than 0.02° in a disturb dual rejection circuit,which was one time higher than that of a disturb observer when the carrier moved at a maximum rate of 4°/s angular velocity with a 12 rad/s frequency sinusoidal.

A four-axis & five-gimbal stable platform on moving vehicle was generated against the extreme horizontal disturb, and it was composed of one level horizontal stable platform and two level two-axis & three- gmibal stable platform which offer twice rejection to vehicle horizontal disturb. Though kinematic and dynamics characteristic analysis, stabilizing models of the horizontal stable platform, the two-axis & three- gimbal stable platform and the whole four-ax!s & five-gimbal stable platform were set up. Finally, the stable performance of the platform was simulated on the three typical environment of vehicle. The results indicate that the max error of the four-axis & five-gimbal stable platform is half of the two-axis three- gimbal platform.

In this paper,25 mm thick poplar flooring blanks from Suqian,Jiangsu Province were chosen to compare the drying quality between the conventional drying and air-kiln combined drying.The results showed that the combined drying,which first lowered the moisture contention of poplar wood down to 25% by air drying and then shifted to kiln drying,could avoid drying defects such as end checks,collapse and warp with the same drying efficiency.

Aimed at addressing the insufficient knowledge of carrier moving coupling description and the failure of the mathematical model of carrier angular velocity coupling to reflect the principle of angular velocity transference,this paper presents an analysis of the change of friction torque and electromagnetism torque with carrier rotation through theoretical modeling,and the principle of angular velocity transference under closed loop control action.The paper stresses that there occurs 1∶1 transference from carrier angular velocity to the platform under strapdown stabilized platform while there is no 1∶1 transference under direct stabilized platform.The paper features the carrier movement angular velocity coupling mathematical model with rotation matrix element of 1 on strapdown stabilized platform and of 0 on direct stabilized platform.The results provide theoretical basis for effective isolation scheme of carrier angular motion.

A multiple tracking control method was generated to improve the tracking performance of a servo system. The multiple tracking control structure, system characteristic on ideal condition and the effect of multiple tracking parts were researched. The results show that when it is applied in opto-electrical tracking servo system, it raises system type and improved the tracking precision. A cubic tracking control which made a V type system is designed. The tracking precision of a servo system on the cubic tracking control reaches 1′, which is 30 times higher than that of a PI control when the target moves at a maximum rate of 50 (°)/s angular velocity with a maximum of 30 (°)/s 2 angular acceleration.

A suppositional compound-axis system was generated for an ordinary electro-optical tracking platform without a fast-steering mirror based on the principles and rules of an equivalent compound-axis system. It was composed of a suppositional platform, suppositional detector, and actual tracking platform. Its system structure was completely the same as a compound-axis system. The suppositional detector arithmetic and object characteristics of the suppositional platform were calculated so that the suppositional system could be realized and an equivalent compound control method could be established. At last the traditional PI control, PI with velocity delay compensation, and the two-dimensional PI control were analyzed and compared. During simulation, tracking precision of a two-dimensional PI control based on the equivalent compound control was 16 times higher than that of a PI control and 3.7 times higher than a PI control with velocity delay compensation. The steady state error was less than 1′ when the target moved at a maximum rate of 10°/s angular velocity with a maximum of 5°/s 2 angular acceleration.

This paper introduced some basic concepts for CPU simulation systems,presented the Flash technology and its advantages and inevitability in the teaching field.The OBB and the Action Script were used to solve the class hierarchy of components and its display problems,the interaction problems of system,signal synchronization and the animation show problems.Finally.the experiment of CPU simulation was realized through the various systems to design coopertiveely.

Under the open-loop condition without external sensing devices,the step-handling walking with relative step height of 10%leg length is realized on a planar bipedal robot Stepper-2D by using virtual slope walking.In order to study the disturbance rejection of virtual slope walking,the ground step disturbance is introduced.Based on the relationship between the pre and post system section states during the step-handling process,it is proved that the step disturbance can be transformed into the perturbation of initial system states and good performance of disturbance rejection of virtual slope walking comes from the stabilizing mechanism of the fixed point.Based on the analysis on the system section states during the transition process,the necessary and sufficient condition for the system to recover from the step disturbance is obtained, further the effect of leg length shorten ratioβ,instantaneous extension angleθ_Ⅱ~* and inter-leg angle(?)_0 on the maximal relative step height is investigated,and the theoretical explanation for the experimental results of 10%leg length step handling walking is then presented.

Compound-axis system is effective on high accuracy tracking in opto-electric servo system. Multiple suppositional compound-axes system is generated for ordinary electro-optical platform without fast-steering mirror device, not for compound-axis system is system. Structure of multiple compound-axes is prolongation of compound-axis system. Its suppositional detectors and object characteristic of suppositional platforms are carried out, so the multiple suppositional compound-axes system can be realized. Thus forms a type of equivalent multiple feed forward control method. Simulation shows tracking accuracy under four-dimension P controller base on the multiple feed forward control is 8.6 times as PI controller and 2.4 times as PI controller with rate delay compensation.

The intermediates and transition structures in the degenerate thermal rearrangements of bicyclo[4.4.0]deca-2,4,7,9-tetraene (1c), bicyclo[5.5.0]dodeca-2,4,8,10-tetraene (11b), and bicyclo[5.4.0]undeca-2,4,8,10-tetraene (14) have been located by (U)B3LYP/6-31G(d) calculations. The singlet-triplet energy differences (ΔE(ST)) in the diradical intermediates (tricyclo[4.4.0.0(2,7)]deca-3,8-dien-5,10-diyl (2c), tricyclo[5.5.0.0(5,11)]dodeca-2,8-dien-4,10-diyl (12b), and tricyclo[5.4.0.0(5,11)]undeca-2,8-dien-4,10-diyl (15)) have been computed, using both UB3LYP and (6/6)CASPT2 calculations. ΔE(ST) in 2c, in which a four-membered ring is anti-bridged by two allylic radicals, is computed to be larger by a factor of 5 than ΔE(ST) in 15, in which the anti-bridged ring is five-membered, and by a factor of 10 than that in 12b, in which the anti-bridged ring is six-membered. The reasons for the much larger interaction between two allylic radicals through the bonds of the four-membered ring in 2c than through the bonds of the five-membered ring in 15 or the six-membered ring in 12b are discussed, and the consequences of the large, through-bond stabilization of the singlet state of 2c are described.