27 research outputs found

    The Study on Mechanical Model Considering Optimal Self-Adaption in the Bottleneck Area

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    It aims to solve the problem that the evacuation state of pedestrians depicted by the traditional social force model in a crowded multiexit scenario has a relatively large difference with the actual state, especially the \u27optimal path\u27 considered by the self-driving force is the problem of shortest path, and the multiexit evacuation mode depicted by the \u27herd behavior\u27 is the local optimum problem. Through in-depth analysis of actual evacuation data of pedestrians and causes of problem, a new crowd evacuation optimization model is established in order to effectively improve the simulation accuracy of crowd evacuation in a multi-exit environment. The model obtains the direction of motion of pedestrians using a field model, fully considers the factors such as exit distance, distribution of pedestrians and regional crowding degree, makes a global optimization for the self-driving force in the social force model using a centralized and distributed network model, and makes a local optimization for it using an elephant herding algorithm, so as to establish a new evacuation optimization method for optimal self-adaption in the bottleneck area. The performance status is compared between the improved social force model and the new model by experiments, and the key factors that affect the new model are analyzed in an in-depth manner. The results show that the new model can optimize the optimal path choice at the early stage of evacuation and improve the evacuation efficiency of pedestrians at the late stage, so as to ensure relatively even distribution of pedestrians at each exit, and also make the simulated evacuation process be more real; and the improvement in overall evacuation efficiency is greater when the number of pedestrians to be evacuated is larger. Therefore, the new model provides a method to solve the phenomenon of disorder in overall pedestrian evacuation due to excessive crowd density during the process of multi-exit evacuation

    Afatinib combined with anti-PD1 enhances immunotherapy of hepatocellular carcinoma via ERBB2/STAT3/PD-L1 signaling

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    BackgroundAfatinib is mainly used to treat advanced non-small cell lung cancer, but its therapeutic effect on hepatocellular carcinoma is still unclear.MethodsOver 800 drugs were screened by CCK8 technology and afatinib was found to have a significant inhibitory effect on liver cancer cells. The expression of PDL1 in tumor cells treated with drugs were detected by qRT-PCR and Weston Blot experiments. The effects of afatinib on the growth, migration and invasion of HCC cells were evaluated using wound healing, Transwell, and cell cloning assays. The in vivo effects of afatinib in combination with anti-PD1 were evaluated in C57/BL6J mice with subcutaneous tumorigenesis. Bioinformatics analysis was performed to explore the specific mechanism of afatinib's inhibition of ERBB2 in improving the expression level of PD-L1, which was subsequently verified through experiments.ResultsAfatinib was found to have a significant inhibitory effect on liver cancer cells, as confirmed by in vitro experiments, which demonstrated that it could significantly suppress the growth, invasion and migration of HCC cells. qRT PCR and Weston Blot experiments also showed that Afatinib can enhance the expression of PD-L1 in tumor cells. In addition, in vitro experiments confirmed that afatinib can significantly enhance the immunotherapeutic effect of hepatocellular carcinoma. Afatinib’s ability to increase PD-L1 expression is mediated by STAT3 activation following its action on HCC cells.ConclusionAfatinib enhances PD-L1 expression in tumor cells through the STAT3/PD-L1 pathway. The combination of afatinib and anti-PD1 treatment significantly increases the immunotherapeutic effect of HCC

    A Study on Crowd Evacuation Model Considering Squeezing Equilibrium in Crowded Areas

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    A new crowd evacuation model is established to solve the stagnation problem of traditional social force models in a complex and dense scene. In the proposed model the acting forces between pedestrians, and between pedestrians and obstacles in the traditional social force model, are improved to find out the relationship in the two cases which are within the influence range and are not intersected, and those which are intersected and not greater than the maximum degree of squeezing, and to solve it for parameter optimization. The simulation platform built is used to compare the performance of the traditional social force model and the improved model, and to deeply analyze the relationship between the evacuation time and the degree of squeezing. The results show that as the evacuation time increases, the crowd in the emergency exit area is getting denser, the optimized model is distributed more evenly, and the probability of squeezing is lower. The optimized model has better stability in terms of the ability to control the intersection without exceeding the maximum degree of squeezing. Due to less squeezing, the optimized model can reduce the time of passing through the exit to a large extent. Therefore, the way to resolve the disorderly evacuation of pedestrians caused by excessive crowd density in the evacuation process is to solve optimization parameters

    Adaptable Hybrid Beamforming with Subset Optimization Algorithm for Multi-User Massive MIMO Systems

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    The exploiting of hybrid beamforming (HBF) in massive multiple-input multiple-output (MIMO) systems can enhance the system’s sum rate while reducing power consumption and hardware costs. However, designing an effective hybrid beamformer is challenging, and interference between multiple users can negatively impact system performance. In this paper, we develop a scheme called Subset Optimization Algorithm-Hybrid Beamforming (SOA-HBF) that is based on the subset optimization algorithm (SOA), which effectively reduces inter-user interference by dividing the users set into subsets while optimizing the hybrid beamformer to maximize system capacity. To validate the proposed scheme, we constructed a system model that incorporates an intelligent reflecting surface (IRS) to address obstacles between the base station (BS) and the users set, enabling efficient wireless communication. Simulation results indicate that the proposed scheme outperforms the baseline by approximately 8.1% to 59.1% under identical system settings. Furthermore, the proposed scheme was applied to a classical BS–users set link without obstacles; the results show its effectiveness in both mmWave massive MIMO and IRS-assisted fully connected hybrid beamforming systems

    A Study on Crowd Evacuation Model Considering Squeezing Equilibrium in Crowded Areas

    No full text
    A new crowd evacuation model is established to solve the stagnation problem of traditional social force models in a complex and dense scene. In the proposed model the acting forces between pedestrians, and between pedestrians and obstacles in the traditional social force model, are improved to find out the relationship in the two cases which are within the influence range and are not intersected, and those which are intersected and not greater than the maximum degree of squeezing, and to solve it for parameter optimization. The simulation platform built is used to compare the performance of the traditional social force model and the improved model, and to deeply analyze the relationship between the evacuation time and the degree of squeezing. The results show that as the evacuation time increases, the crowd in the emergency exit area is getting denser, the optimized model is distributed more evenly, and the probability of squeezing is lower. The optimized model has better stability in terms of the ability to control the intersection without exceeding the maximum degree of squeezing. Due to less squeezing, the optimized model can reduce the time of passing through the exit to a large extent. Therefore, the way to resolve the disorderly evacuation of pedestrians caused by excessive crowd density in the evacuation process is to solve optimization parameters

    TNFα-Mediated Necroptosis Aggravates Ischemia-Reperfusion Injury in the Fatty Liver by Regulating the Inflammatory Response

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    Nonalcoholic fatty liver disease (NAFLD) is more sensitive to ischemia and reperfusion injury (IRI), while there are no effective methods to alleviate IRI. Necroptosis, also known as “programmed necrosis,” incorporates features of necrosis and apoptosis. However, the role of necroptosis in IRI of the fatty liver remains largely unexplored. In the present study, we aimed to assess whether necroptosis was activated in the fatty liver and whether such activation accelerated IRI in the fatty liver. In this study, we found that the liver IRI was enhanced in HFD-fed mice with more release of TNFα. TNFα and supernatant of macrophages could induce necroptosis of hepatocytes in vitro. Necroptosis was activated in NAFLD, leading to more severe IRI, and such necroptosis could be inhibited by TN3-19.12, the neutralizing monoclonal antibody against TNFα. Pretreatment with Nec-1 and GSK′872, two inhibitors of necroptosis, significantly reduced the liver IRI and ROS production in HFD-fed mice. Moreover, the inhibition of necroptosis could decrease ROS production of hepatocytes in vitro. Inflammatory response was activated during IRI, and necroptosis inhibitors could suppress signaling pathways of inflammation and the soakage of inflammation cells. In conclusion, TNFα-induced necroptosis played an important role during IRI in the fatty liver. Our findings demonstrated that necroptosis might be a potential target to reduce the fatty liver-associated IRI
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