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Objective To study the influence of air springs on maglev train system as one of the components, and solve the problem of deteriorated suspension performance in maglev train system due to the influence of air springs, the mechanism research and simulation analysis of the above problem are carried out. Method First, a maglev model without air springs is built, and based on this, a control algorithm is designed. According to the performance indicators of the maglev system, the optimal control parameters are designed. After determining the control algorithm and optimal control parameters, the influence of air springs is considered in the maglev system model to study the influence of air spring stiffness on maglev suspension performance. The performance of the maglev system is simulated using MATLAB software. During the simulation process, the air spring stiffness is changed without changing the control parameters, and the changes in maglev suspension performance are observed. When the maglev suspension performance deteriorates, the optimal suspension performance is maintained through optimizing control parameters. Result & Conclusion Simulation results show that the air spring stiffness is within a certain range, and the greater the stiffness, the less conducive to the maglev system stability. When the air spring stiffness increases, increasing the stiffness and damping of the control system appropriately is beneficial for the stability of the maglev system.

A highly efficient separation method for trace plutonium from high uranium plutonium ratio samples was established by combining two Reillex anion exchange chromatographic columns. The effects of resin type, wash condition, valence state adjustment on plutonium separation were investigated, and the conditions of separation process were determined. When the mass ratio of uranium to plutonium in the feed liquid is 106, after two-stage Reillex column separation, the average yield of plutonium is 99.35% and the decontamination factor of uranium is greater than 107. Using this process, high purity trace 239Pu is separated from irradiated uranium target, and the atomic ratio of (238U+238Pu)/239Pu is (3.60±1.15)×10-5(n=6).

Introduction The purpose of this study was to determine whether TLR4 knockdown induced by miRNA-140-5p improves tendinopathy in an in vitro experiment. Material and methods Extraction of tendon-derived stem cells (TDSCs) from SD rats was performed using TGF-β1 to develop a tendinopathy cell model. In the first step, we knocked down TLR4 by si-TLR4 to investigate TLR4 in tendinopathy development, and the next we used miRNA-140-5p to investigate miRNA-140-5p in tendinopathy development. The inflammatory factors and Hyp concentration were evaluated by ELISA assay; the cell viability was measured by MTT assay; the cell apoptosis was evaluated by TUNEL and/or flow cytometry. The relative mRNA was measured by RT-qPCR assay; the relative proteins expression was evaluated by cellular immunofluorescence and/or WB assay. The correlation between miRNA-140-5p and TLR4 was analyzed by Luciferase reporter assay. Results With miRNA-140-5p overexpression or TLR4 knockdown, the cell viability was significantly increased with cell apoptosis depressing compared with the Model group (p < 0.05, respectively). Meanwhile, the inflammatory factors TNF-α, IL-1β and IL-6 and Hyp concentration were significantly improved (p < 0.05, respectively), whereas the TLR4, MyD88 and NF-B(p65) protein expression levels were significantly depressed with TLR4 knockdown by si-TLR4 or miRNA-140-5p which target TLR4. Conclusions The present results showed that TLR4 knockdown induced by miRNA-140-5p or si-TLR4 improved tendinopathy in an in vitro cell experiment.

Simple Summary: This study reports the development of a triplex RT-qPCR assay for the simultaneous detection of Porcine Epidemic Diarrhea Virus (PEDV), Transmissible Gastroenteritis Virus (TGEV), and Porcine Kobuvirus (PKV) by targeting the conserved regions of their respective genes. The assay was optimized for specificity, sensitivity, and reproducibility, and demonstrated no cross-reactivity with other pathogens. It was validated against the Chinese standard single-assay method, exhibiting complete consistency in detecting these viruses in clinical samples. Finally, testing of 1502 clinical diarrhea samples revealed significant prevalence rates of PEDV, TGEV, and PKV, with mixed infections being common. The pathogens responsible for porcine viral diarrhea are diverse, causing significant economic losses to the pig industry. PEDV and TGEV are well-known pathogens causing diarrheal diseases in pigs, leading to significant economic losses in the breeding industry. In contrast, the newly identified diarrhea virus, PKV, has not garnered as much attention. However, co-infection of PKV with PEDV results in more severe symptoms in piglets, such as acute gastroenteritis, and promotes increased replication of PEDV. Rapid and accurate diagnosis of viral diarrhea is essential for farms to identify pathogens early and mitigate economic losses. This study describes the development of a triplex real-time fluorescent quantitative RT-qPCR technique that can simultaneously detect three RNA viruses associated with porcine viral diarrhea: PEDV, TGEV, and PKV. To establish the triplex RT-qPCR method for the simultaneous detection and identification of the above three diarrhea viruses, conserved regions of the M gene of TGEV, the N gene of PEDV, and the 3D gene of PKV were selected to design specific primers and probes. After optimizing the reaction conditions, the method's specificity, sensitivity, and reproducibility were evaluated. The triplex RT-qPCR method did not show a significant difference in PCR efficiency compared to the single RT-qPCR method. The method is specific to TGEV, PKV, and PEDV, exhibits no cross-reactivity with other pathogens, and demonstrates satisfactory sensitivity and reproducibility; the limit of detection (LOD) of PEDV, TGEV, and PKV is 11.42 copies/μL. Furthermore, the performance of the triplex RT-qPCR assay was compared with the Chinese standard single-assay method for detecting TGEV, PKV, and PEDV, showing complete consistency between the two methods (100% compliant). Subsequently, 1502 clinical diarrhea samples were collected from the Guangxi Zhuang Autonomous Region to investigate the local prevalence of TGEV, PKV, and PEDV and the positive rates were 16.38% (246/1502), 1.46% (22/1502), and 45.14% (678/1502), respectively. Co-infection of PEDV and PKV were most common, with a rate of 12.12% (182/1502). This study presents a valuable method for the rapid and simultaneous identification of PEDV, TGEV, and PKV in clinical animal farming practices, and provides a reassessment of the epidemiology of these diarrhea-causing viral pathogens in the Guangxi Zhuang Autonomous Region. [ABSTRACT FROM AUTHOR]

Ultrasonic focusing transducers have broad prospects in advanced ultrasonic non-destructive testing fields. However, conventional focusing methods that use acoustic concave lenses can disrupt the acoustic impedance matching condition, thereby adversely affecting the sensitivity of the transducers. In this paper, an active focusing planar ultrasonic transducer is designed and presented to achieve a focusing effect with a higher sensitivity. An electrode pattern consisting of multiple concentric rings is designed, which is inspired by the structure of Fresnel Zone Plates (FZP). The structural parameters are optimized using finite element simulation methods. A prototype of the transducer is manufactured with electrode patterns made of conductive silver paste using silk screen-printing technology. Conventional focusing transducers using an acoustic lens and an FZP baffle are also manufactured, and their focusing performances are comparatively tested. The experimental results show that our novel transducer has a focal length of 16 mm and a center frequency of 1.16 MHz, and that the sensitivity is improved by 23.3% compared with the conventional focusing transducers. This research provides a new approach for the design of focusing transducers. [ABSTRACT FROM AUTHOR]