Search

Background: Ultrasound (US) is mostly used for diagnostic purpose but could be used for cancer treatments with a US intensity or frequency fitted to such a purpose. Prostate cancer (PC) has the highest prevalence in the urological field, but indications for immune checkpoint inhibitors (ICIs) for PC are limited to very few cases. In this study, we compared the antitumor effect of US irradiation alone with the combined use of US and ICIs in vitro and in vivo. Methods: PC cell line TRAMP-C2 cells were used in our experiments. TRAMP-C2 cells were irradiated with US with pulse repeated frequencies (PRF) of 1, 10, and 100 Hz. Cell proliferation was evaluated by MTS assay and apoptotic cells were analyzed using flow cytometry. To verify the antitumor effect of US irradiation on PC in vivo, we conducted animal experiments using mice. TRAMP-C2-bearing mice were irradiated with US with PRF of 10 and 100 Hz. Three weeks after the start of US irradiation, anti-PD-1 antibody was administered to the mice. Finally, mice were sacrificed and tumors were collected. Immunohistochemical (IHC) analyses were assessed for cleaved caspase-3 and CD3 in tumor cell extracts. Results: Cell proliferation assays showed that 1 and 10 Hz US significantly inhibited cell survival (p < 0.0001). In addition, US irradiation induced apoptosis at 1, 10, and 100 Hz (p = 0.0129, p = 0.0150, and p = 0.0017, respectively). In animal experiments, a significant tumor growth inhibitory effect was observed at 10 and 100 Hz, and 100 Hz + ICIs (p < 0.05, respectively). Hematoxylin–eosin (H–E) staining showed a significant increase in the necrotic area of the tumor at 100 Hz and 100 Hz + ICIs (p < 0.05, respectively). In addition, under IHC staining the expression level of cleaved caspase-3 and the number of CD3-positive cells increased at 100 Hz (p < 0.05, respectively). Conclusion: US irradiation induced apoptosis in cells and reduced cell viability. In vivo tumor growth was suppressed by combined treatment with US irradiation and ICIs. Further research on immune system activation will lead to less invasive and more efficient treatments for PC.

The electromagnetic radiation emission model of motor drive System for electric vehicles (EVs) is presented in this paper. First, the radiation electromagnetic interference (EMI) mechanism of the motor drive system is analyzed and investigated by experiment. The radiation EMI mainly comes from the common mode current flowing along the three phase cable between the inverter and the motor. Secondly, the feasibility of the finite element method (FEM) is verified by calculating the wire electromagnetic field around and the radiation EMI model of the motor drive system is established using the FEM. The simulation and experimental results show that the proposed model is feasible.

In this paper, the electric impendence sensor is simulated calculation with COMSOL Multiphysics. The relationship between impedance and x-displacement of air cavity, the relationship between impedance and y-displacement of air cavity, and the relationships between impedance and radius of air cavity are obtained.

Transformer vibration research is an effective diagnosis of DC bias fault. The vibration signal acquired is actually the mix signal of vibration from both the core and windings, and this makes it difficult to analyze the above two separately. Therefore the paper presents a new approach to separate vibration signal of core and windings by Fast-ICA algorithm. The simulated results of core and windings vibration are given and compared with experiment test. Comparative analysis verify that transformer vibration in no-load is core vibration and vibration in short circuit is windings vibration. Transformer vibration signals under different DC bias are tested by experiment. Vibration signals are separated by Fast-ICA algorithm. Core vibration signal and windings vibration signal are respectively obtained. The research lays the groundwork for further research of transformer DC bias vibration.

Probe-type electrostatic sensors provide a novel and applicable way to realize on-line condition monitoring of heat engines. However, researches on this type of electrostatic sensors are still scanty, especially needs more detailed studies for the sensors sensing characteristics. In this paper, a simulative 3-D model with high fidelity was established using COMSOL, by which a detailed research on probe-type electrostatic sensors spatial sensitivity was conducted, the whole spatial sensitivity distribution on the centre section and conclusions about the influencing factors of spatial sensitivity were acquired. The simulative results were confirmed by experiments, and can be used for optimal design of probe-type electrostatic sensors.

In this paper, the terminal sliding mode (TSM) control technique is used to solve the solution sought for the maximum power point tracking (MPPT) of wind energy conversion system. In order to realize the control strategy, the wind energy conversion system (WECS) is regarded as a part of the constructed high order system. Based on the constant tip-speed ratio (TSR), selecting the appropriate state variables and treating rotational speed as the object researched, the control scheme for the MPPT of wind turbine can be achieved by using the terminal sliding mode control technique. The simulation carried out shows that the system tracking efficiency can be greatly improved and the power factor and tip speed ratio are very close to the optimal value in this solution.

In this paper, a method for conducted electromagnetic interference (EMI) prediction in Electric Vehicle motor drive system based on components’ circuit models is presented. Firstly, the characteristics of the components are analyzed and the equivalent circuits are drew; then, the parasitic parameters of the electromagnetic device are extracted by the measurement, analytical solution and finite element method (FEM); and finally, the circuit model of the whole motor drive system in high frequency range is established. This model is verified by the measurement and simulation results in the frequency domain.

In this paper, the first order buoyancy force of ferrofluid is simulated calculation under external magnetic field in ferrofluid devices. The relationship between first order buoyancy force and displacement of nonmagnetic body under different relative permeability of ferrofluid，and the relationship between first order buoyancy force and relative permeability of ferrofluid are obtained.

It is very important for accurately grasping stress, strain, and metal flow during the hollow motor shaft rolling, and it is also foundation of forming regularity, rolling force and energy parameter. The cross wedge rolling process of hollow motor shaft was simulated through rigid-plastic finite element software deform-3D. According to the simulation results, the distribution of internal stress, strain field inside the second step of the motor shaft had been obtained, revealed the metal flow ruler for the second step during forming process and it could effected on the metal flow ruler for the first step.

Rolling force is the main parameters for calculating the intensity and rigidity of the main parts in the mill. To determine the force produced by the four roll rolling process, the finite element (FE) model for hollow motor shaft forming using 4-roll cross wedge rolling had been established for forming analysis with the aid of FE software Deform-3D. According to the results of FE simulation, the rolling load rules were obtained and maximum force of up to 60 KN. It has important theoretical significance and application value for the mill equipment designing and die structure optimization.

Soil-Rock Mixture (SRM) is a unique type of geological material characterized by inhomogeneous composition and complicated structures. This paper investigated the fracture mechanisms that govern the strength and deformation of SRM subjected to uniaxial compression loads by means of computed tomography (CT) techniques. The self-designed loading devices and self-developed image processing program were applied to identify and quantify the fractures inside SRM during compressions. The results show that the internal fracture behavior of SRM greatly depends on the rock ratios of SRM.

Currently specific discharge point cannot be effectively located using common electrometric methods of generator stator winding partial discharge online monitoring. To solve the problem an electrical-sound joint detection method has been proposed. Since accuracy of location would be heavily affected by time delay of ultrasonic wave propagation, background noise and spectrum of partial discharge ultrasonic signal were analyzed first, and ultrasound field distribution and ultrasonic wave propagation were also stimulated. Moreover, an ultrasonic sensors distribution method was proposed to reduce the delay estimation error. The method was verified by field experiments. Experimental results showed that the theoretical analysis was exact and the sensor distribution method was feasible, thus laying foundation for further realizing large generator partial discharge Ultrasonic wave on line monitoring and location.

Video-oculography (VOG) is a non-invasive method used for the eye tracking detecting. A most important work of VOG is to accurately estimate the pupil center. However, VOG cannot acquire eye movement when the eye blinks. A Grey forecasting model was proposed to predict the pupil center for the blinking frame of VOG video. The Grey forecasting model used GM(1,1) model to carry on the modeling. Then an experiment is provided. The experiment results show that the predicted data of the Grey forecasting meet the characteristics of the patients with nystagmus. The Grey forecasting model is a viable means of accurately predict the pupil center for blinking in VOG.

In this paper, a remote Distribution Transformer (DT) monitoring system is presented and developed to solve the problems of existing remote monitoring system wiring too much, too complicated, fault diagnosing and maintaining difficulty. The system hardware design based on 16 bit PIC18F458 chip and GSM module TC35i is proposed. The system software design with MySQL and Visual C++6.0 are discussed in detail. A real-time monitoring of parameters such as three-phase voltage, current, power factor and transformer temperature is finally realized. Experiment results show that the system possesses accurate data gathering, strong anti-interference and good operation performance.

Objective: To observe the effect of emodin on the biological behavior of human fibroblasts (FB) in culture of kidney in patients with lupus nephritis (LN).Methods: FB were isolated from kidney culture of LN patients, and the effect of emodin on3H-TdR incorporated rate of FB was observed. The apoptosis and c-myc gene expression were detected in the same way by flow cytometry.Results: Emodin could markedly inhibit the proliferation of human kidney FB, and inducing cell apoptosis through up-regulating c-myc gene expression in human renal FB.Conclusion: Emodin can inhibit proliferation and promote apoptosis of FB, which may be important in ameliorating interstitial fibrosis, and thus improve prognosis of LN.