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Targeting the chromatin structural changes of antitumor immunity
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作者 Nian-nian Li Deng-xing Lun +22 位作者 Ningning Gong Gang Meng Xin-ying Du he wang Xiangxiang Bao Xin-yang Li Ji-wu Song Kewei Hu Lala Li Si-ying Li Wenbo Liu Wanping Zhu Yunlong Zhang Jikai Li Ting Yao Leming Mou Xiaoqing Han Furong Hao Yongcheng Hu Lin Liu Hongguang Zhu Yuyun Wu Bin Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期460-482,共23页
Epigenomic imbalance drives abnormal transcriptional processes,promoting the onset and progression of cancer.Although defective gene regulation generally affects carcinogenesis and tumor suppression networks,tumor imm... Epigenomic imbalance drives abnormal transcriptional processes,promoting the onset and progression of cancer.Although defective gene regulation generally affects carcinogenesis and tumor suppression networks,tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes,which may have significant implications for the development and application of epigenetic therapy,cancer immunotherapy,and their combinations.Herein,we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes,DNA methylation,histone post-translational modification,and chromatin structure in tumor immunogenicity,and introduce these epigenetic research methods.We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immuno-therapy through the complex interaction between cancer epigenetics and cancer immunology. 展开更多
关键词 Antitumor immunity Chromatin structural Cancer epigenetics DNA methylation Histone modification CHEMOTHERAPY
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Single-atom photo-catalysts:Synthesis,characterization,and applications
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作者 Siqi Li Ziwang Kan +4 位作者 he wang Jiaxiao Bai Yunyi Liu Song Liu Yingjie Wu 《Nano Materials Science》 EI CAS CSCD 2024年第3期284-304,共21页
Single-atom catalysts(SACs)are gaining popularity in catalytic reactions due to their nearly 100%atomic utilization and defined active sites,which provide great convenience for studying the catalytic mechanism of cata... Single-atom catalysts(SACs)are gaining popularity in catalytic reactions due to their nearly 100%atomic utilization and defined active sites,which provide great convenience for studying the catalytic mechanism of catalysts.However,SACs still present challenges such as complex formation processes,low loading and easy agglomeration of catalysts.Herein,we systematically discuss the synthesis methods for SACs,including coprecipitation,impregnation,atomic layer deposition,pyrolysis and Anti-Ostwald ripening etc.Various techniques for characterizing single-atom catalysts(SACs)are described in detail.The utilization of individual atoms in various photocatalytic reactions and their mechanisms of action in different reactions are explained.The purpose of this review is to introduce single-atom synthesis methods,characterization techniques,specific catalytic action and their applications in the direction of photocatalysis,and to provide a reference for the industrialization of photocatalytic single-atoms,which is currently impossible,in the hope of promoting further development of photocatalytic single-atoms. 展开更多
关键词 PHOTOCATALYSIS Single atom Catalytic mechanism
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Research on Scheduling Strategy of Flexible Interconnection Distribution Network Considering Distributed Photovoltaic and Hydrogen Energy Storage
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作者 Yang Li Jianjun Zhao +2 位作者 Xiaolong Yang he wang Yuyan wang 《Energy Engineering》 EI 2024年第5期1263-1289,共27页
Distributed photovoltaic(PV)is one of the important power sources for building a new power system with new energy as the main body.The rapid development of distributed PV has brought new challenges to the operation of... Distributed photovoltaic(PV)is one of the important power sources for building a new power system with new energy as the main body.The rapid development of distributed PV has brought new challenges to the operation of distribution networks.In order to improve the absorption ability of large-scale distributed PV access to the distribution network,the AC/DC hybrid distribution network is constructed based on flexible interconnection technology,and a coordinated scheduling strategy model of hydrogen energy storage(HS)and distributed PV is established.Firstly,the mathematical model of distributed PV and HS system is established,and a comprehensive energy storage system combining seasonal hydrogen energy storage(SHS)and battery(BT)is proposed.Then,a flexible interconnected distribution network scheduling optimization model is established to minimize the total active power loss,voltage deviation and system operating cost.Finally,simulation analysis is carried out on the improved IEEE33 node,the NSGA-II algorithm is used to solve specific examples,and the optimal scheduling results of the comprehensive economy and power quality of the distribution network are obtained.Compared with the method that does not consider HS and flexible interconnection technology,the network loss and voltage deviation of this method are lower,and the total system cost can be reduced by 3.55%,which verifies the effectiveness of the proposed method. 展开更多
关键词 Seasonal hydrogen storage flexible interconnection AC/DC distribution network photovoltaic absorption scheduling strategy
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Dynamic Economic Scheduling with Self-Adaptive Uncertainty in Distribution Network Based on Deep Reinforcement Learning
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作者 Guanfu wang Yudie Sun +5 位作者 Jinling Li Yu Jiang Chunhui Li Huanan Yu he wang Shiqiang Li 《Energy Engineering》 EI 2024年第6期1671-1695,共25页
Traditional optimal scheduling methods are limited to accurate physical models and parameter settings, which aredifficult to adapt to the uncertainty of source and load, and there are problems such as the inability to... Traditional optimal scheduling methods are limited to accurate physical models and parameter settings, which aredifficult to adapt to the uncertainty of source and load, and there are problems such as the inability to make dynamicdecisions continuously. This paper proposed a dynamic economic scheduling method for distribution networksbased on deep reinforcement learning. Firstly, the economic scheduling model of the new energy distributionnetwork is established considering the action characteristics of micro-gas turbines, and the dynamic schedulingmodel based on deep reinforcement learning is constructed for the new energy distribution network system with ahigh proportion of new energy, and the Markov decision process of the model is defined. Secondly, Second, for thechanging characteristics of source-load uncertainty, agents are trained interactively with the distributed networkin a data-driven manner. Then, through the proximal policy optimization algorithm, agents adaptively learn thescheduling strategy and realize the dynamic scheduling decision of the new energy distribution network system.Finally, the feasibility and superiority of the proposed method are verified by an improved IEEE 33-node simulationsystem. 展开更多
关键词 SELF-ADAPTIVE the uncertainty of sources and load deep reinforcement learning dynamic economic scheduling
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Progress in pathogenesis and treatment of type A hepatic encephalopathy in acute liver failure:a comprehensive review
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作者 Ye-Xin Xu he wang +4 位作者 Kang-Rui Hu Bo-Yu Shen Lin Xie Guang-Ji wang Yan Liang 《Pharmacology Discovery》 2024年第1期1-11,共11页
Hepatic encephalopathy is a serious neuropsychiatric complication caused by liver failure,which is characterized by the development of cognitive and motor disorders into coma.Typically,hepatic encephalopathy can be di... Hepatic encephalopathy is a serious neuropsychiatric complication caused by liver failure,which is characterized by the development of cognitive and motor disorders into coma.Typically,hepatic encephalopathy can be divided into three types(A,B,and C)according to the etiology.Type A hepatic encephalopathy(AHE)caused by acute liver failure seriously affects the prognosis of patients,ranging from mild neuropsychological changes to coma,brain edema,and even death.So far,the research on the pathogenesis of AHE has focused on the toxic effects of ammonia on the central nervous system,metabolic disorders(glutamine and lactate accumulation),neurotransmission alteration,systemic inflammation,especially neuro-inflammation.All these mechanisms are not independent,but mutually have synergistic effects.In clinic,treatment of AHE based on only one mechanism is often ineffective.To clarify the pathogenesis and the interaction among the mechanisms will be beneficial to the effective treatment of AHE and reduce the mortality.The aim of this review is to provide comprehensive scientific evidence for the clinical treatment of AHE via collecting and analyzing the latest mechanism of AHE,and clarifying the relationship among these mechanisms combing the investigation of the latest research progress of drug treatment of acute liver failure.Consequently,we find that the pathogenesis of AHE is a complex neurocognitive disorder shaped by interactions among hyperammonemia,inflammation,and changes in neurotransmission,the signaling pathways thereby integrating the inflammatory and neurological inputs to impact pathophysiological or neurobehavioral outcomes. 展开更多
关键词 type A hepatic encephalopathy AMMONIA GLUTAMINE lactate inflammation blood-brain barrier neurotransmission
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基于径向气隙磁密和定子电流的永磁同步电机均匀退磁故障诊断研究 被引量:1
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作者 丁石川 何旺 +1 位作者 杭俊 汤德伟 《中国电机工程学报》 EI CSCD 北大核心 2024年第1期332-340,I0027,共10页
该文提出一种基于径向气隙磁密和定子电流的永磁同步电机均匀退磁故障诊断方法。首先,建立电机的d轴等效磁路模型,分析均匀退磁故障后径向气隙磁密的变化规律;然后,获取电机的径向气隙磁密和定子电流信号,对各极下径向气隙磁密幅值进行... 该文提出一种基于径向气隙磁密和定子电流的永磁同步电机均匀退磁故障诊断方法。首先,建立电机的d轴等效磁路模型,分析均匀退磁故障后径向气隙磁密的变化规律;然后,获取电机的径向气隙磁密和定子电流信号,对各极下径向气隙磁密幅值进行归一化处理,并绘制雷达图,根据雷达图和比较相同定子电流幅值下健康电机和故障电机的各极下径向气隙磁密幅值的平均值,来诊断均匀退磁故障;利用空载各极下径向气隙磁密幅值的平均值计算故障程度。最后,仿真和实验结果均验证所提均匀退磁故障诊断方法的有效性。 展开更多
关键词 均匀退磁故障 永磁同步电机 径向气隙磁密 定子电流 d轴等效磁路
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Hypermethylation of thymosinβ4 predicts a poor prognosis for patients with acute-on-chronic hepatitis B liver failure
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作者 he wang Yan-Ping Yin +4 位作者 Zhen-Li wang Yu Qian Yu-Chen Fan Hui-Hui Liu Kai wang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第4期373-382,共10页
Background:It has been demonstrated that thymosinβ4(Tβ4)could inflect the severity of acute-on-chronic hepatitis B liver failure(ACHBLF),but the relationship between its methylation status and the prognosis of liver... Background:It has been demonstrated that thymosinβ4(Tβ4)could inflect the severity of acute-on-chronic hepatitis B liver failure(ACHBLF),but the relationship between its methylation status and the prognosis of liver failure is not clear.This study aimed to determine Tβ4 promoter methylation status in patients with ACHBLF and to evaluate its prognostic value.Methods:The study recruited 115 patients with ACHBLF,80 with acute-on-chronic hepatitis B pre-liver failure(pre-ACHBLF),and 86 with chronic hepatitis B(CHB).In addition,there were 36 healthy controls(HCs)from the Department of Hepatology,Qilu Hospital of Shandong University.The 115 patients with ACHBLF were divided into three subgroups:33 with early stage ACHBLF(E-ACHBLF),42 with mid-stage ACHBLF(M-ACHBLF),and 40 with advanced stage ACHBLF(A-ACHBLF).Tβ4 promoter methylation status in peripheral blood mononuclear cells(PBMCs)was measured by methylation-specific polymerase chain reaction,and mRNA was detected by quantitative real-time polymerase chain reaction.Results:Methylation frequency of Tβ4 was significantly higher in patients with ACHBLF than in those with pre-ACHBLF,CHB or HCs.However,expression of Tβ4 mRNA showed the opposite trend.In patients with ACHBLF,Tβ4 promoter methylation status correlated negatively with mRNA levels.The 3-month mortality of ACHBLF in the methylated group was significantly higher than that in the unmethylated group.Also,Tβ4 promoter methylation frequency was lower in survivors than in non-survivors.When used to predict the 1-,2-,and 3-month incidence of ACHBLF,Tβ4 methylation status was better than the model for end-stage liver disease(MELD)score.The predictive value of Tβ4 methylation was higher than that of MELD score for the mortality of patients with E-ACHBLF and M-ACHBLF,but not for A-ACHBLF.Conclusions:Tβ4 methylation might be an important early marker for predicting disease incidence and prognosis in patients with ACHBLF. 展开更多
关键词 Acute-on-chronic hepatitis B liver failure Acute-on-chronic hepatitis B pre-liver failure Thymosinβ4 METHYLATION PROGNOSIS
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Modified constraint-induced movement therapy enhances cortical plasticity in a rat model of traumatic brain injury:a resting-state functional MRI study
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作者 Cheng-Cheng Sun Yu-Wen Zhang +10 位作者 Xiang-Xin Xing Qi Yang Ling-Yun Cao Yu-Feng Cheng Jing-wang Zhao Shao-Ting Zhou Dan-Dan Cheng Ye Zhang Xu-Yun Hua he wang Dong-Sheng Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期410-415,共6页
Modified constraint-induced movement therapy(mCIMT)has shown beneficial effects on motor function improvement after brain injury,but the exact mechanism remains unclear.In this study,amplitude of low frequency fluctua... Modified constraint-induced movement therapy(mCIMT)has shown beneficial effects on motor function improvement after brain injury,but the exact mechanism remains unclear.In this study,amplitude of low frequency fluctuation(ALFF)metrics measured by resting-state functional magnetic resonance imaging was obtained to investigate the efficacy and mechanism of mCIMT in a control co rtical impact(CCI)rat model simulating traumatic brain injury.At 3 days after control co rtical impact model establishment,we found that the mean ALFF(mALFF)signals were decreased in the left motor cortex,somatosensory co rtex,insula cortex and the right motor co rtex,and were increased in the right corpus callosum.After 3 weeks of an 8-hour daily mClMT treatment,the mALFF values were significantly increased in the bilateral hemispheres compared with those at 3 days postoperatively.The mALFF signal valu es of left corpus callosum,left somatosensory cortex,right medial prefro ntal cortex,right motor co rtex,left postero dorsal hippocampus,left motor cortex,right corpus callosum,and right somatosensory cortex were increased in the mCIMT group compared with the control cortical impact group.Finally,we identified brain regions with significantly decreased mALFF valu es at 3 days postoperatively.Pearson correlation coefficients with the right forelimb sliding score indicated that the improvement in motor function of the affected upper limb was associated with an increase in mALFF values in these brain regions.Our findings suggest that functional co rtical plasticity changes after brain injury,and that mCIMT is an effective method to improve affected upper limb motor function by promoting bilateral hemispheric co rtical remodeling.mALFF values correlate with behavio ral changes and can potentially be used as biomarkers to assess dynamic cortical plasticity after traumatic brain injury. 展开更多
关键词 amplitude of low frequency fluctuation cortical plasticity functional magnetic resonance imaging modified constraint-induced movement therapy traumatic brain injury
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基于动物实验系统评价大黄素治疗糖尿病肾病的可行性 被引量:2
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作者 何望 黄国顺 +1 位作者 张凯钰 周恩超 《海南医学院学报》 CAS 北大核心 2024年第6期451-462,共12页
目的:系统评价大黄素对糖尿病肾病动物肾脏的保护作用。方法:计算机检索中国知网、维普、万方、中国生物医学文献及PubMed等数据库,检索从建库至2023年2月25日关于大黄素治疗糖尿病肾病的动物实验。采用RevMan 5.4.1软件进行分析。结果... 目的:系统评价大黄素对糖尿病肾病动物肾脏的保护作用。方法:计算机检索中国知网、维普、万方、中国生物医学文献及PubMed等数据库,检索从建库至2023年2月25日关于大黄素治疗糖尿病肾病的动物实验。采用RevMan 5.4.1软件进行分析。结果:共纳入14个研究,结果显示,相比于对照组,大黄素组更能降低糖尿病动物血糖[SMD=-2.51,95%CI(-3.77,-1.24),I^(2)=89%]、肌酐[SMD=-3.05,95%CI(-4.75,-1.34),I^(2)=91%]、尿素氮[SMD=-2.69,95%CI(-3.88,-1.50),I^(2)=82%]、24 h尿蛋白定量[SMD=-3.35,95%CI(-4.85,-1.85),I^(2)=87%]、相对肾重[SMD=-7.72,95%CI(-12.55,-2.88),I^(2)=90%]、三酰甘油[SMD=-1.24,95%CI-1.94,-0.54),I^(2)=0%]等指标。而大黄素与对照组在胆固醇[SMD=-1.19,95%CI(-2.29,-0.55),I^(2)=77%]等方面的差异无统计学意义。同时Meta分析提示大黄素保护肾脏与nephrin的表达、相关信号通路等有关。此类研究相关的严重不良反应鲜有报道。结论:大黄素对糖尿病肾病动物肾脏有保护作用,但有待于更高质量、严谨规范的大样本临床试验进一步证实。 展开更多
关键词 大黄素 糖尿病肾病 动物实验 系统评价
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磷酸苄酯和亚磷酸苄酯衍生物与二氧化碳的电化学羧化反应
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作者 刘晓菲 王贺 +3 位作者 陶力 任伟民 吕小兵 张文珍 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第9期73-76,共4页
二氧化碳是无毒、储量丰富、廉价易得的可再生能源,以二氧化碳作为碳源,将其催化转化为高附加值的化学品比如羧酸化合物,对实现碳循环可持续利用具有重要的意义。由于二氧化碳的热力学稳定性和动力学惰性,传统的二氧化碳参与的羧化反应... 二氧化碳是无毒、储量丰富、廉价易得的可再生能源,以二氧化碳作为碳源,将其催化转化为高附加值的化学品比如羧酸化合物,对实现碳循环可持续利用具有重要的意义。由于二氧化碳的热力学稳定性和动力学惰性,传统的二氧化碳参与的羧化反应通常需要苛刻的反应条件。与经典的有机合成方法相比,有机电化学合成利用电能驱动反应,不需要额外的化学氧化剂或还原剂,是更安全、可持续和环保经济的有机合成方法。其中,碳卤键或碳杂键与二氧化碳的电化学还原羧化反应可高效获得高附加值羧酸化合物。磷酸酯作为一种良好的离去基团广泛应用于众多有机合成反应。本文发展了在牺牲阳极及非牺牲阳极两种体系中磷酸苄酯和亚磷酸苄酯衍生物与二氧化碳的电化学羧化反应高效合成重要的芳基乙酸类化合物。该反应表现出优异的官能团耐受性,高效且容易放大,为布洛芬、非诺洛芬等芳基乙酸类药物分子提供了一种高效经济绿色的合成方法。通过循环伏安实验和多组对照实验证实磷酸苄酯和亚磷酸苄酯底物在阴极还原生成的苄基自由基和碳负离子是反应关键中间体,同时也不能排除二氧化碳在阴极还原生成CO_(2)^(·-)的可能性。 展开更多
关键词 电化学羧化反应 非牺牲阳极反应 二氧化碳 磷酸苄酯 芳基乙酸
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基于MobileNetV2-DeepLabv3+的混凝土坝水下裂缝语义分割模型
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作者 何旺 钮新强 +1 位作者 田金章 朱延涛 《水利水电科技进展》 CSCD 北大核心 2024年第6期106-112,共7页
为解决深度学习算法难以有效检测混凝土坝水下裂缝的问题,构建了基于MobileNetV2-DeepLabv3+的混凝土坝水下裂缝语义分割模型。该模型引入轻量化网络MobileNetV2,同时将深层特征下采样倍数降为8,以提高小数据集工况下的识别准确率和推... 为解决深度学习算法难以有效检测混凝土坝水下裂缝的问题,构建了基于MobileNetV2-DeepLabv3+的混凝土坝水下裂缝语义分割模型。该模型引入轻量化网络MobileNetV2,同时将深层特征下采样倍数降为8,以提高小数据集工况下的识别准确率和推理速度;将交叉熵损失函数与Dice损失函数的组合作为模型的损失函数,以缓解类别不平衡问题。工程实例验证结果表明:该模型在测试集上的平均像素准确率和平均交并比分别高达90.87%和86.33%,满足水下裂缝语义分割精度要求;典型工况下的混凝土坝水下裂缝的分割效果优于其他对比模型,泛化能力强;模型具有内存占比小、推理速度快的特点,可用于混凝土坝水下裂缝的检测。 展开更多
关键词 混凝土坝 水下裂缝 MobileNetV2-DeepLabv3+ 语义分割 机器视觉
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基于代理双向竞拍的弹性云资源调度方案
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作者 何望 林果园 《计算机应用与软件》 北大核心 2024年第3期87-93,共7页
针对跨云平台的资源调度问题,提出一种基于代理双向竞拍的弹性资源调度方案。该方案在拍卖过程中引入交易延时排队影响因子,排队轮数越多,排队影响因子值越大,竞价提交优先级越高,同时根据服务等级协议判定不合规交易的惩罚金数额,以惩... 针对跨云平台的资源调度问题,提出一种基于代理双向竞拍的弹性资源调度方案。该方案在拍卖过程中引入交易延时排队影响因子,排队轮数越多,排队影响因子值越大,竞价提交优先级越高,同时根据服务等级协议判定不合规交易的惩罚金数额,以惩罚金制度防范恶意竞拍交易的出现。每轮竞拍允许并发实现多项交易。仿真结果表明,该方案保证了竞拍成功率,并且与传统一次拍卖成交方案相比,其竞拍时间减少了0.32 s,同时能提高16%的用户收益与9%的资源提供商利益。 展开更多
关键词 双向竞拍 资源调度 排队影响因子 恶意竞拍
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Survey and clinical considerations of gender identity in lower primary school children 被引量:1
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作者 Ya-Lin Zhang Hong-Mei Zhang +3 位作者 Jing-Xia Xu Qi-Ying Zhou he wang Xiao-Cheng Pan 《World Journal of Psychiatry》 SCIE 2024年第1期36-43,共8页
BACKGROUND Gender consciousness directly affects the development of gender identity,which is a continuous and lifelong process.Meanwhile,hospitalization is a part of many children's lives and has an impact on thei... BACKGROUND Gender consciousness directly affects the development of gender identity,which is a continuous and lifelong process.Meanwhile,hospitalization is a part of many children's lives and has an impact on their gender development.AIM To investigate the current situation of gender identity in lower primary school children by conducting a survey of 202 hospitalized children in the lower grades and to provide a theoretical basis and foundation for the cultivation of gender identity and medical treatment of children based on the results.This study aims to inspire clinical medical staff to scientifically and reasonably arrange hospital wards for lower primary school children and pay attention to gender protection during the medical treatment process and to help children shape a unified and clear gender identity,which will enable them to better integrate into society and promote their personality development.METHODS The gender consciousness scale for elementary and middle school students was RESULTS Gender identity was already present in lower primary school children.The children's gender roles and gender equality consciousness were strong,exceeding the critical value,but their gender characteristics,gender identity,and gender ideal consciousness were weak.Children aged 6 had the weakest gender identity,and girls had significantly stronger gender identity than boys.CONCLUSION Gender identity is already present in lower primary school children,providing a basis and inspiration for the cultivation of gender identity and medical treatment of lower primary school children.Clinical medical staff should be aware of and understand these results and should scientifically and reasonably arrange hospital wards for lower primary school children. 展开更多
关键词 School-age children Gender consciousness Gender identity HOSPITALIZATION Gender weakening
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Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats
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作者 Yunting Xiang Xiangxin Xing +6 位作者 Xuyun Hua Yuwen Zhang Xin Xue Jiajia Wu Mouxiong Zheng he wang Jianguang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1495-1504,共10页
Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected limb.However,differences among reconstruction strategies at the brain network lev... Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected limb.However,differences among reconstruction strategies at the brain network level have not been elucidated.This study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve transfer.Sprague–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper trunk.Resting-state brain functional magnetic resonance imaging was obtained 7 months after surgery.The independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the component.Alterations in intra-network resting-state functional connectivity were compared among the groups.Target muscle reinnervation was assessed by behavioral observation(elbow flexion)and electromyography.The results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural pathway.Nerve repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor representation.The thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve transfer.Brain areas related to cognition and emotion were enhanced after end-to-side nerve transfer.Our study revealed important brain networks related to different nerve reconstructions.These networks may be potential targets for enhancing motor recovery. 展开更多
关键词 brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity
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Extending microwave-frequency electric-field detection through single transmission peak method
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作者 刘青 陈进湛 +6 位作者 王赫 张杰 阮伟民 伍国柱 郑顺元 罗景庭 宋振飞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期417-423,共7页
The strength of microwave(MW)electric field can be observed with high precision by using the standard electromagnetically induced transparency and Aulter–Towns(EIT-AT)technique,when its frequency is resonant or nearl... The strength of microwave(MW)electric field can be observed with high precision by using the standard electromagnetically induced transparency and Aulter–Towns(EIT-AT)technique,when its frequency is resonant or nearly-resonant with the Rydberg transition frequency.As the detuning of MW field increases,one of the transmission peaks(single peak)is easier to measure due to its increased amplitude.It can be found that the central symmetry point of the two transmission peaks f_(1/2)is only related to the detuning of MW field△_(MW)and central symmetry point f_(0)of resonant MW field,satisfying the relation f_(1/2)=△_(MW)/2+f_(0).Thus,we demonstrate a single transmission peak method that the MW E-field can be determined by interval between the position of single peak and f_(1/2).We use this method to measure continuous frequencies in a band from-200 MHz to 200 MHz of the MW field.The experimental results and theoretical analysis are presented to describe the effectiveness of this method.For 50 MHz<△_(MW)<200 MHz,this method solves the problem that the AT splitting cannot be measured by using the standard EIT-AT techniques or multiple atomic-level Rydberg atom schemes. 展开更多
关键词 microwave electric field Rydberg atom electromagnetically induced transparency(EIT) Aulter-Towns splitting
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“兼容型城镇化”与“新三元结构”——一种解释和分析中国新阶段城镇化的新视角与新框架
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作者 贺旺 《城市规划》 CSSCI CSCD 北大核心 2024年第8期25-34,共10页
随着中国经济社会发展进入新阶段,农业转移人口正在经历从远距离迁徙向近域流动转变,从满足家庭生计需要向更高质量发展转变,从公共服务不足向城乡公共服务兼容共享转变。从“人的城镇化”出发,提出“兼容型城镇化”的概念,即动态生活... 随着中国经济社会发展进入新阶段,农业转移人口正在经历从远距离迁徙向近域流动转变,从满足家庭生计需要向更高质量发展转变,从公共服务不足向城乡公共服务兼容共享转变。从“人的城镇化”出发,提出“兼容型城镇化”的概念,即动态生活于城市和乡村之间,生产生活方式具有城乡双栖、工农兼业特征,同时享有城市和乡村公共服务的城镇化形态。兼容型城镇化还具有灵活就业、就地非农化、职住空间耦合等特征。这一现象受到城乡二元制度框架下的“推拉均衡”机制、以家庭分工合作为基础的城乡兼容型家庭机制、以文明素质提升和社会跃迁为表征的人的现代化机制的共同作用。案例分析表明,兼容型城镇化包括以特大城市功能外溢为基础的就地兼容型城镇化和以县城为载体的就近兼容型城镇化两种模式。当前,城乡之间呈现出以兼容型城镇化为特征的“新三元结构”,引导和促进这个“第三元”健康有序发展,有利于协同推动新型城镇化和乡村振兴,促进城乡融合发展,最终实现城乡一体化。 展开更多
关键词 兼容型城镇化 城乡双栖 工农兼业 新三元结构
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Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump
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作者 he wang Ying he 《Fluid Dynamics & Materials Processing》 EI 2024年第4期889-899,共11页
Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the inf... Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices. 展开更多
关键词 Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying
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Magneto-optic Kerr Effect Measurement of TbMn_(6)Sn_(6) at mK Temperature
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作者 黄代强 汪洋 +2 位作者 王贺 王健 刘阳 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期159-163,共5页
Novel electron states stabilized by Coulomb interactions attract tremendous interests in condensed matter physics.These states are studied by corresponding phase transitions occurring at extreme conditions such as mK ... Novel electron states stabilized by Coulomb interactions attract tremendous interests in condensed matter physics.These states are studied by corresponding phase transitions occurring at extreme conditions such as mK temperatures and high magnetic field.In this work,we introduce a magneto-optical Kerr effect measurement system to comprehensively explore these phases in addition to conventional transport measurement.This system,composed of an all-fiber zero-loop Sagnac interferometer and in situ piezo-scanner inside a dilution refrigerator,operates below 100 m K,with a maximum field of 12 Tesla and has a resolution as small as 0.2μrad.As a demonstration,we investigate TbMn_(6)Sn_(6),where the manganese atoms form Kagome lattice that hosts topological non-trivial Dirac cones.We observed two types of Kerr signals,stemming from its fully polarized ferromagnetic ground state and positive charged carriers within the Dirac-like dispersion. 展开更多
关键词 INTERFEROMETER SCANNER system
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A Disturbance Localization Method for Power System Based on Group Sparse Representation and Entropy Weight Method
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作者 Zeyi wang Mingxi Jiao +4 位作者 Daliang wang Minxu Liu Minglei Jiang he wang Shiqiang Li 《Energy Engineering》 EI 2024年第8期2275-2291,共17页
This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sp... This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sparse representation and entropy weight method.Three different electrical quantities are selected as observations in the compressed sensing algorithm.The entropy weighting method is employed to calculate the weights of different observations based on their relative disturbance levels.Subsequently,by leveraging the topological information of the power system and pre-designing an overcomplete dictionary of disturbances based on the corresponding system parameter variations caused by disturbances,an improved Joint Generalized Orthogonal Matching Pursuit(J-GOMP)algorithm is utilized for reconstruction.The reconstructed sparse vectors are divided into three parts.If at least two parts have consistent node identifiers,the node is identified as the disturbance node.If the node identifiers in all three parts are inconsistent,further analysis is conducted considering the weights to determine the disturbance node.Simulation results based on the IEEE 39-bus system model demonstrate that the proposed method,utilizing electrical quantity information from only 8 measurement points,effectively locates disturbance positions and is applicable to various disturbance types with strong noise resistance. 展开更多
关键词 Disturbance location compressed sensing group sparse representation entropy power method GOMP algorithm
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Risk-Balanced Routing Strategy for Service Function Chains of Cyber-Physical Power System Considering Cross-Space Cascading Failure
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作者 he wang Xingyu Tong +2 位作者 Huanan Yu XiaoHu Jing Bian 《Energy Engineering》 EI 2024年第9期2525-2542,共18页
Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat t... Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat to the safety and reliability of CPPS,and there is an acute need to reduce the probability of these failures.Towards this end,this paper first proposes a cascading failure index to identify and quantify the importance of different information in the same class of communication services.On this basis,a joint improved risk-balanced service function chain routing strategy(SFC-RS)is proposed,which is modeled as a robust optimization problem and solved by column-and-constraint generation(C-CG)algorithm.Compared with the traditional shortest-path routing algorithm,the superiority of SFC-RS is verified in the IEEE 30-bus system.The results demonstrate that SFC-RS effectively mitigates the risk associated with information transmission in the network,enhances information transmission accessibility,and effectively limits communication disruption from becoming the cause of cross-space cascading failures. 展开更多
关键词 Cyber-physical power system service function chain risk balance routing optimization cascading failure
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