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Rubber isolator is commonly used as vibration isolation device for piston pump, and the vibration of piston pump can be effectively reduced by adjusting the dynamic stiffness of rubber isolator. In this paper, in order to study the effect of rubber isolator's dynamic stiffness on the dynamic of seawater hydraulic piston pump (SWHPP), four kinds of rubber isolators with different dynamic stiffness were selected. An experimental modal analysis (EMA) experiment was conducted to study the influence of rubber isolator's dynamic stiffness on the natural frequency of SWHPP. The experimental results indicated that the natural frequency of the pump structure decreased as the dynamic stiffness of rubber isolator increased. Then, the influence of the rubber isolator's dynamic stiffness on the vibration of SWHPP was further studied, and conclusions can be obtained that: the vibration level of the pump decreases with the dynamic stiffness of rubber isolator increases. For the four kinds of rubber isolators, when the dynamic stiffness of rubber isolator is 5800N/cm, the vibration reduction effect of the isolator is the best, which reaching 38%. In addition, the dynamic stiffness of rubber isolator mainly affects the vibration of the pump in the frequency of 0–20 Hz.

Lysine Acetyltransferase 2B (KAT2B) functions pivotally in regulating chromatin organization as well as function, and is a key regulator of signal transduction during development of many diseases, like tumors. This research intends to exploit expression, clinical significance as well as how KAT2B functions in cervical cancer. Our study showed that the KAT2B expression in cervical carcinoma tissues was inferior to that in normal tissues; decreased KAT2B expression was signally related to increased T staging, lymph node metastasis together with tissue differentiation; patients with high KAT2B expression had better prognosis. After knocking down KAT2B, cell proliferation diminished with decreased cell migration and invasion. Additionally, knocking down KAT2B made for increasing EMT-related proteins N-cadherin and Vimentin expression, while ZO-1 expression decreased; overexpression had the opposite effect. Dual luciferase analysis affirmed that miR-93-5p could in specifical bind to KAT2B, and thus reducing its expression and activity. KAT2B may be a new cervical tumor-suppressor gene, which is closely concerned with poor prognosis of patients, and under negative regulation by miR-93-5p., Graphical Abstract

Shuping Cao,1,* Hongxia Li,2,* Lei Li3 1Department of Gynecology, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China; 2Department of Obstetrics, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China; 3Department of Pathology, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lei LiDepartment of Pathology, Dongying District People’s Hospital, No. 333, Jinan Road, Dongying, Shandong, 257000, People’s Republic of ChinaTel/Fax +86-546-8990136Email lilei65825@163.comPurpose: Cervical cancer is a great threat to women’s health all over the world. Non-coding RNAs performed a wide range of functions. This study aimed to clarify the clinical significance and biological function of lncRNA SNHG17 and miRNA-375-3p (miR-375-3p) in cervical cancer (CC).Patients and Methods: Blood samples from 124 CC patients and 119 healthy volunteers were collected. The relative expression of SNHG17 and miR-375-3p in CC patient serums and cells was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). The receiver operating curve (ROC) was plotted for diagnostic value estimation. The CCK-8 and transwell assay were conducted to explore the function of SNHG17 on CC cells. A luciferase reporter assay was carried out to confirm the interaction of SNHG17 and miR-375-3p. Rescue experiments were performed to verify the interaction.Results: SNHG17 showed an ascending expression while miR-375-3p descended in the serum of CC patients. For SNHG17 and miR-375-3p, respectively, the AUC was 0.863 and 0.869, the sensitivity was 84.7% and 75.8%, and the specificity was 78.2% and 86.6%. Knockdown of SNHG17 inhibited proliferation, migration, and invasion of CC cells. Serum SNHG17 expression was negatively correlated with miR-375-3p expression, and miR-375-3p was the target miRNA of SNHG17. Rescue experiments verified the knockdown of SNHG17 inhibited cell growth through repressing miR-375-3p expression.Conclusion: SNHG17 and miR-375-3p have the potential to be diagnostic markers for CC. Overexpression of SNHG17 in CC promoted the progression of CC partly via targeting miR-375-3p, implying a novel therapeutic target for CC emerging.Keywords: lncRNA SNHG17, miR-375-3p, clinical significance, biological function, cervical cancer

An investigation into the dynamic behavior of the piston pump is an important method to reduce its vibration and noise. In this paper, an approach to predict the dynamics of a seawater hydraulic piston pump (SWHPP) from output-only transmissibility measurements is introduced. In order to eliminate the harmonic interference generated by spindle rotation, the excitation in this method is the pressure which caused by the SWHPP operating at a constant speed and under different loading conditions. The first four modes of the SWHPP were estimated utilizing the method proposed in this paper, and the influence of the pressure on the dynamics of the SWHPP structure was further studied. The experimental results indicated that peak occurred around the frequency of 20 Hz, and the reason is that the estimated second-order natural frequency (19.8 Hz) is near to the frequency of 20 Hz which is the excitation frequency of the swash plate and the flat valve of the SWHPP. In addition, this method can identify modal parameters of the piston pump structure in the working state, so it can effectively predict the dynamic behaviors of the piston pump.

Maneuverability is one of the most important performances of underwater vehicles. To improve the maneuverability of underwater vehicles, a high-pressure waterjet propulsion system combined with a Thrust Vector Control System (TVCS) was presented, which controlled the sailing trajectory through adjusting the waterjet deflection angle and thrust vector instead of rudders and sterns. The TVCS was established in the form of 3RPS Parallel Manipulator and the position feedback was provided by measuring the displacements of three actuator cylinders. The relationship between the thrust direction and the displacements of the actuator cylinders was established through the procedure of solving an inverse kinematics problem. Simultaneously, the motion transformation function of the system was derived, and the Fuzzy-PID strategy was adopted. Accordingly, the Simulink model was built, and the simulation indicated that the system had good performance. In addition, the sailing trajectory was obtained, and the results showed that the turning diameter was 78 m, and it was independent of thrust and sailing speed. The underwater vehicle utilizing high-pressure water jet propulsion with TVCS had good maneuverability at either high or low speed conditions.

Hydropneumatic suspension has the characteristics of nonlinear stiffness, nonlinear friction damping, and nonlinear hydraulic damping, and therefore, it has been widely applied to heavy vehicles. A hydropneumatic suspension with a special structure was proposed and studied in this paper. The nonlinear quarter-vehicle model was built by using Newton’s laws according to its configuration. Then, this nonlinear mathematic model was linearized through the statistical linearization method on the basis of random vibration theory. Next, the transfer functions of the suspension system subjected to random road excitation were built according to the statistical linearization model and the power density spectrum approach. In addition, the responses of vehicle body acceleration, tire relative dynamic load, and suspension deflection with respect to the wideband random excitation due to road roughness were obtained according to the James formula. Next, the influences of the equivalent damping ratio and the equivalent frequency ratio on vehicle riding comfort, riding safety, handing stability, and suspension reliability were analyzed through simulations. These results provided the basic principles for selecting the reasonable hydropneumatic suspension parameters.

Water jet propulsion is a crucial technology for ships and underwater vehicles. A high-pressure water jet propulsion system was proposed in this paper. The fundamental thrust theory of this system was studied and the influence of cavitation on the thrust was investigated. First, the mathematical model of thrust based on momentum equation coupled with cavitation theory was established. Then, the performance of cavitation two-phase flow field was simulated through computational fluid dynamics (CFD), and the thrust was calculated according to these simulation results. Finally, experiments were conducted on a test rig to study its force performance. The experimental results showed that the maximum thrust reached 4000 N with a 16-mm nozzle at the flow rate of 1200 L/min. The experimental results were both higher than the simulation and the calculation results. The theoretical force model coupled with the cavitation model was better matched with the experimental results.

Few effective insulation state detection methods for power capacitor can be used in field. In this paper, a power capacitor insulation state detection method based on polarization-depolarization current is proposed. Firstly, the basic principles of the method are discussed. Then, two characterized parameters are conducted based on polarization and depolarization currents, which are DC conductivity and 0.1Hz dielectric loss. A test device based on this method is developed to evaluate the insulation state of power capacitor with different aging conditions. The test results showed that the polarization and depolarization currents increased along with the aging conditions. The DC conductance and 0.1Hz dielectric loss also increased along with the aging conditions. The test indicated the polarization-depolarization current method is suitable for power capacitor insulation state detection.

Electro-Hydraulic Proportional Directional Valve (EHPDV) is a key component in an electro-hydraulic proportional control system. Erosion-abrasion caused by solid particles within the oil is one of the major concerns in hydraulic control valves which may result in equipment malfunction and even failure. In this paper, the erosion-abrasion of a sliding spool of EHPDV was researched through Computational Fluid Dynamic (CFD) simulation and the analysis consists of three steps: the continuous phase flow field simulation, particle tracking, and erosion calculation. Therefore, a three dimensional model of the valve was built and the grid was meshed by use of ICEM. Then, a coupled Eulerian-Lagrangian approach was employed to solve the liquid-particle flow characteristics within the EHPDV, the Erosion/Corrosion Research Center (E/CRC) erosion model and the Grant empirical formula of particle-wall rebound models were utilized to predict the erosion rate. The simulation results indicated that the average erosion rate of the sliding spool would nonlinearly various with the valve opening. In addition, the maximum and average erosion rate of the sliding spool would gradually increase with the velocity. 10 µm is the critical diameter, and the erosion rate would decrease with the increases of the particle diameter if the particle diameter is above 10 µm and inversely when the diameter is below 10µm. Based on the simulation results, an erosion prediction model of sliding spool was further proposed, which provides a theoretical principle for forecasting the lifecycle of EHPDV.

Centrifugal pumps are widely used in modern industry, and blades are the key parts of it. The cracks on blades may result in a very serious consequence. In this paper, a fault diagnosis method based on principal component analysis (PCA) and Gaussian mixed model (GMM) was proposed, which combined signal processing and knowledge. Also, the theory model of proposed methods was established, and Expectation Maximization (EM) algorithm was used to make the model converge. PCA was used to reduce the data dimensionalities and increase the feature resolution, and GMM was used as classifier for crack fault. In order to verify the diagnostic effect of the model, the experimental bench of centrifugal pump was established, and various working conditions of the centrifugal pump were simulated. Experimental results showed that the classifier based on these parameters performed very well in data testing.

With the development of data science, there are more and more ways to dig for patterns hidden in the data. If we can apply the advanced model of data science to the power data, we can mine the potential value of power data. In this paper, the monitoring and inspection data of 110kV main transformers and related basic environmental data are fused to establish conditional inference tree model and AdaBoost algorithm to evaluate whether the 110kV main transformers have defects and faults. The accuracy of the two algorithms is compared. Finally, we select the AdaBoost algorithm with higher accuracy for building the 110kV main transformer fault evaluating model. This paper provides a reference for the automatic detection of power grid faults, and provides new ideas for the application of power grid big data.

The Sino–Zambian Cooperation project provides national catchment sediment geochemical data for 58 elements including Cu and Co from 746 sediment samples at 736 sampling sites, corresponding to a sampling density of about 1 site per 1000 km2. The Cu and Co were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) under strict quality control using field duplicates, standard reference materials and analytical replicate samples. The 95% ranges (2.5%–97.5%) of Cu and Co concentrations were from 1.8 to 57.81 × 10−6 and from 0.54 to 22.83 × 10−6, respectively, reflecting locally unevenness distributions. The median values of Cu and Co are 5.77 × 10−6 and 2.98 × 10−6, respectively. The most noticeable anomalous patterns of Cu and Co are distributed between Lusaka and Solwezi (Lufilian Arc Belt) with the trend of increasing concentrations from southeast to northwest. The all spatial distribution patterns of Cu and Co in tectonic units, drainage basins and geomorphological landscapes show good relations with parent rocks, climate, Cu (Co) deposits and smelting plants in Lufilian Arc Belt. The Cu and Co concentrations show metallogenic belts in Mkushi area, between Lusaka and Solwezi areas, and in Livingstone area.

Counterfeits in the medicine market make the authentication of snakes used for Chinese medicine a challenge to Chinese drug regulatory control agencies. This paper explores existing methods that can be used to quickly and accurately distinguish Zaocys (Z. dhumnades) from its counterfeits for routine identification of snake meats in food and drug control laboratories. In this research, the Cytochrome Oxidase I (COI) fragments of 51 samples from 17 species of snakes were amplified using Polymerase Chain Reaction (PCR) and sequenced. The inter- and intra-specific variations of COI sequences were analyzed and compared based on Kimura-2-parameter (K-2P) distances; the minimal interspecific K-2P distance was 0.0934, which was bigger than the maximum intraspecific K-2P distance in Z. dhumnades (0.0523), indicating that Zaocys can be separated from its counterfeits. The Neighbor-Joining (N-J) tree of the snakes was constructed and the results show that snakes of the same species cluster with 100% bootstrap values. Since the Zaocys and its counterfeits are of different species, they can be distinguished using the N-J tree method. Another 10 samples of Zaocys from markets and drug stores were identified at the species level, among which 5 samples were proven to be the counterfeits--Ptyas korros.

According to the function and operating characteristics of water hydraulic relief valves in a high-pressure water pipe system, a novel one-stage relief valve with a one-way damper was designed and analyzed in this study. The one-way damper consists of a damping chamber and a check valve. Moreover, a damping orifice is bored along the axis of the check-valve spool. When the main spool moves to open the valve port, the check valve is fully open, and the damping orifice generates no damping force on the main spool; otherwise, the check valve is completely closed, and the damping orifice produces a damping force on the main spool. Furthermore, based on a mathematical model describing the dynamic characteristics of the relief valve, the effect of the one-way damper on the dynamic characteristics of the relief valve was simulated and analyzed, and certain optimal parameters of the one-way damper were obtained (e.g., the diameter and length of the damping orifice and the initial volume of the damping chamber). Lastly, the experimental results obtained from a prototype of the relief valve, which was manufactured to the optimal dimensions, demonstrated that the pressure overshoot was 7.5%, the response time was 1.43 × 10−2 s, and the transition time was 3.9 × 10−2 s. Thus, the one-way damper could significantly improve the dynamic characteristics of the relief valve.

A non-contact optical approach to measure the in-plane displacement of an object is introduced in this paper. Through a ste of optical system, the image of the object to be measured is formed in the image plane of the CCD. When the object moves in-plane, its image moves in the image plane of the CCD accordingly. Consequently, the displacement of the object can be detected in real-time by measuring the movement of its image with CCD. The prosed w\system is suitable for non-contact measurement such as deformation of objects in high temperature, deformation of elastic objects and low frequency mechanical vibration. It can be widely used in mechanics experiments to achieve high precision measurement in long working distance.

Here a new flash phase-shifting method has been prosed. In this method, the phase difference between three consecutive Moire images is achieved by changing the illumination angles. A theoretical derivation is presented, and certain formulas are obtained to calculate 3D information of the measured object. The special phase unwrapping algorithm connected with this phase shifting method is also solved out. At last, experiment result have been given to compare with theory derivation.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.