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When traffic congestion caused by accidents occurs on urban roads, the current signal control scheme may face failure. It is necessary to establish an effective dynamic route guidance scheme and formulate a reasonable signal timing scheme to alleviate the impact of the accident on urban traffic. In this paper, traffic congestion is divided into three states and the traffic evacuation strategies are formulated, respectively. Then, on the basis of analyzing the internal mechanism and spatiotemporal variation of queuing at intersections, a two-stage model is proposed to optimize the signal timing parameters. In the first stage, the basic timing parameters of each intersection, such as signal cycle and green ratio, are obtained. In the second stage, the offset optimization model is constructed to minimize the total delay time of the coordinated phase of all detour routes in the control scope, considering the early dissipation of queuing vehicles at the entrance of the intersection. This model is solved with a particle swarm optimization algorithm and simulated to the actual road network with VISSIM. As the experimental results show, this control method can greatly reduce the average vehicle delay, stop times, queue length, and the number of vehicles passing.

Implementation of proportional-integral (PI) controllers in synchronous reference frame (SRF) is a well-established current control solution for electric drives. It is a general and effective method in digital control as long as the ratio of Sampling to Fundamental (S2F) frequency ratio, rS2F, remains sufficiently large. When the aforesaid condition is violated, such as operations in high-speed or high-power drives, the performance of the closed-loop system becomes incrementally poor or even unstable. This is due to the cross-coupling of the signal flow between d and q axes, which is introduced by the SRF. In this article, an accurate model of current dynamics which captures the computational delay and PWM characteristics in discrete time domain is developed. This motivates the investigation of eliminating cross-coupling effects in PMSM drive systems. A new current control structure in the discrete time domain is proposed targeting full compensation of cross-coupling effects of SRF whilst improving dynamic stiffness at low S2F ratios. The matching simulation and experimental results carried out on a 5-kW high speed drive corroborate the theoretical analysis.

Using injectable hydrogels loaded with mesenchymal stem cells (MSCs) to repair chondral defects is a new trend of cartilage tissue engineering in recent years. In this study, hyaluronic acid (HA) hydrogels containing the system of sustained-release Kartogenin (KGN) and modified by RGD and HAV peptides were used to facilitate repair of cartilage defect in the knee joint of rabbits. Different groups of implants were injected into osteochondral defects, and samples were taken 4 weeks after operation. Through the qualitative and quantitative analysis of Micro-CT, it can be seen that both FH (unloaded cell group) and R + FH groups (allogeneic cell group) can repair osteochondral defects well, and the amount of bone formation is high, which is close to the intact cartilage groups. Macroscopic observation and histological staining analysis showed that except for the intact cartilage group, FH group obtained the highest score. The morphology of the cartilage tissue in the FH groups was more regular and continuous than that in R + FH and H + FH (xenogeneic cell group) groups, approaching that of native cartilage. Immunohistochemical staining of Collagen II (Col II) showed that the expression and morphology of Col II in FH groups were similar to those in intact cartilage tissue. Interestingly, through in vivo experiments, this functionalized hyaluronic acid hydrogel can effectively promote the rapid repair of rabbit knee cartilage defects within one month.

The blasting vibration has an impact on the rock and soil around the blasting hole and the nearby structures. The vibration-isolating slot is one of the methods to reduce the damage of blasting vibration. In this paper, the influences of the depth and position of the vibration isolation slot on the PPV (peak particle velocity) attenuation characteristics of the ground vibration and blasting vibration damping effect of the vibration isolation slot at different measuring points are studied systematically by LS-DYNA numerical models. The results show that the damping effect of the vibration isolation slot is realized by reflecting the blasting vibration wave and increasing the propagation paths of the blasting vibration wave. When the measuring points are 5 m∼45 m far away from the vibration-isolating slot, the average vibration damping effect of the vibration-isolating slot is more than 30% and the deeper the depth of the vibration isolation slot, the better the vibration damping effect when the measuring points are 5 m∼15 m far away from the vibration isolation slot. However, when the measuring points are 15 m∼45 m far away from the vibration isolation slot, the vibration damping effect is best when the depth of the vibration isolation slot is 15 m. The vibration damping effect of blasting vibration at the same measuring point is different due to different positions of vibration isolation slot. For the measuring points M3 and M5, with the increasing of the distance between the vibration-isolating slot and the explosion source, the vibration damping effect of the vibration-isolating slot shows an increasing-decreasing-increasing trend; however, it shows a decreasing-increasing-decreasing trend for the measuring point M4.

Due to complex working conditions and cuttings migration mechanism and other factors, cuttings bed is easy to form in deviated well section and extended reach horizontal well section, and too high cuttings bed is easy to cause a series of complex downhole accidents, such as bit mud bag, wall collapse, stuck drilling and holding in drilling. The borehole cleaning evaluation system based on cuttings weighing can collect the cuttings returned in real time. The system combines the real-time cuttings flow rate, theoretical cuttings volume, actual cuttings volume and other data to evaluate the borehole cleaning situation and provide guidance for field drilling construction. At the same time, the drilling optimization analysis module is designed in the system. The module adopts the combination of comprehensive logging data and geological logging data, combining the advantages of comprehensive logging and geological logging, which can realize the real-time drilling time optimization analysis to the maximum extent. In this paper, the evaluation system of borehole cleaning based on cuttings weighing is studied and corresponding engineering application examples are given. It has high practical application value for borehole cleaning monitoring and evaluation, drilling aging optimization analysis and reducing non-productive time.

Background: Ovarian cancer is a leading cause of death in gynecological malignancies. Being the most common subtype in OEC, ovarian serious cancer also include two subtypes: low grade serous ovarian cancer[LGSC]and high grade serous ovarian cancer[HGSC] [1]. Purpose: To assess the capability of apparent diffusion coefficient [ADC] histogram analysis and conventional measurements on magnetic resonance imaging [MRI] in differentiating between LGSC and HGSC]. Methods: We retrospectively recruited 38 patients with pathologically proven ovarian serous epithelial cancer . The mean ADC value was measured by one technician using two methods on post-processed workstation. The ADC value and histogram parameter difference between LGSC and HGSC group were compared. The correlation between ADC value and the Ki-67 expression was calculated across both groups. Results: The repeatability of ADC measurements across two methods was good; the ROI method [ADC-roi] had the better performance repeatability than the area method did [ADC-area]. The value of ADC-mean、ADC-min、ADC-max and ADC-area significantly differed between both groups [p < 0.001]. The value of ADC-area correlated inversely with ki-67 expression in the whole group [Pearson coefficient = -0.382, p = 0.02]. The 3D computerized-diagnostic model have the best discriminative performance in determining HGSC than 2D and conventional ADC measurements did. The 3D model yielded a sensitivity of 100%, a specificity of 95.45% and an accuracy of 97.73%. Conclusion: In the present study, the 3D ADC histogram model help to differentiate HGSC from LGSC with the better performance than conventional ADC measurements.

Background: PRMT5 is a major enzyme responsible for the post-translational symmetric demethylation of protein arginine residues, which has been validated as an effective therapeutic target for cancer. Thus, many nucleoside-based PRMT5 inhibitors have been reported in the past year. Objective: To discover a novel series of non-nucleoside PRMT5 inhibitors through a molecular docking-based virtual screening approach. Methods: Our in-house compound library was virtually screened using the Glide program, identifying a new PRMT5 inhibitor 1. Based on the structural similarity of hit 1, a series of structure-oriented derivatives, including 3a-3e, 7a-7g, and 12a-12f, were synthesized and selected for the inhibitory activity evaluation against PRMT5, as well as cytotoxicity against MV4-11 cell. Results: The analogs 7a-7e with benzimidazole core exhibited potent PRMT5 inhibitory activities, with 7e displaying the most potent activity with an IC50 of 6.81 ± 0.12 μM. In the anti-proliferative assay, compound 7e showed a strong inhibitory effect on MV4-11 cell growth. Finally, the binding mode of 7e with PRMT5 was predicted to provide insights for further structural optimization. Conclusion: The newly discovered PRMT5 inhibitors have potential antitumor activity against MV4-11 cells. This work highlighted this series of 3-(1H-benzo[d]imidazol-2-yl)aniline derivatives as novel anti-cancer lead compounds targeting PRMT5, which were worthy of further investigation.

Severe environmental destruction is being driven by excessive resource consumption in the industrial production process. Therefore, there is a necessity to evaluate the sustainability of the production system. In this study, the emergy method has been adopted to assess the flat building glass production in China based on raw material and chemical composition. A series of problems including key contributors, primary sustainable indexes, unit emergy value (UEVs), sensitivity ratios, and waste impact was studied. The results illustrate that (1) the nonrenewable resources and imported resources showed the dominant impacts. (2) Silica sand and sandstone were the foremost items for the raw material angle emergy. (3) Excessive EIR, serious ELR, and tiny ESI were the main contributors to the unsustainability of the evaluated system. (4) Four UEVs were revealed, which are 1.69E + 12sej/kg, 1.80E + 12sej/kg, 1.60E + 12sej/kg, and 1.71E + 12sej/kg, respectively. (5) The nonrenewable resources showed the biggest fluctuation (7.09%), followed by imported resources (1.62%) in view of the raw material perspective; for the chemical composition, the nonrenewable resources were 7.15%, and imported resources were 1.49%, respectively. (6) Waste gas emissions were found as the major emergy contributor to the economic loss. Furthermore, positive solutions were discussed for improving the sustainability of glass production, including the proportion increase of renewable energy, recycling material replacement, and promotion of energy-saving equipment.