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STARE:a new detector array for exploring the breakup reaction mechanisms induced by weakly bound nuclei
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作者 Yan-Song Wu Gao-Long Zhang +12 位作者 Cheng-Jian Lin Nan-Ru Ma lei yang Guang-Xin Zhang Shi-Peng Hu Huan-Qiao Zhang Marco Mazzocco Yong-Jin Yao Zhen-Wei Jiao Ming-Li Wang Xue-Dou Su Hao-Bo Lv Kun Dong 《Nuclear Science and Techniques》 2025年第11期167-176,共10页
A new detector array with a large solid angle coverage for the coincidence measurement of charged fragments was developed to study the breakup reaction mechanisms of weakly bound nuclear systems at energies around the... A new detector array with a large solid angle coverage for the coincidence measurement of charged fragments was developed to study the breakup reaction mechanisms of weakly bound nuclear systems at energies around the Coulomb barrier.The array has been used to explore the breakup reaction mechanisms of^(6,7)Li+^(209)Bi systems at E_(beam)=30,40,47 MeV,showing good performance in particle identification and complete kinematic measurements.Based on this,different breakup modes and breakup components were clearly distinguished,and some new breakup modes were discovered,such as^(7)Li→α+t breakup mode in6Li+209Bi system and^(7)Li→^(6)He+p breakup mode in^(7)Li+^(209)Bi system.This array can also be used to explore other breakup reaction mechanisms induced by weakly bound nuclei. 展开更多
关键词 Detector array Coincidence measurement Breakup reaction Weakly bound nuclei
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基于LSTM模型的重型燃气轮机非线性广义预测控制器设计
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作者 雷扬 杨卓 +1 位作者 左信 岳元龙 《热能动力工程》 北大核心 2026年第2期85-95,共11页
针对T60重型燃气轮机存在的动态特性强非线性、多变量耦合及工况大范围变化等特点,提出一种基于长短期记忆网络(LSTM)的非线性广义预测控制器设计方法。构建了燃气轮机多输入多输出LSTM动态模型,通过互信息法确定时间窗口,采用四分位距... 针对T60重型燃气轮机存在的动态特性强非线性、多变量耦合及工况大范围变化等特点,提出一种基于长短期记忆网络(LSTM)的非线性广义预测控制器设计方法。构建了燃气轮机多输入多输出LSTM动态模型,通过互信息法确定时间窗口,采用四分位距剔除异常值,并对数据进行标准化处理。进一步设计重型燃气轮机的非线性广义预测控制器(NGPC),利用LSTM模型在线预测自由响应并采用数值逼近强制响应以构建动态矩阵,提出基于局部线性化的实时梯度优化策略,将非凸优化问题转化为可实时求解的二次规划子问题,并利用投影梯度下降法实时求解控制率。在MATLAB平台开展仿真实验,选取大范围阶跃负荷为扰动输入、控制周期100 ms。仿真结果表明:在负荷突变时,相比T60燃气轮机用的Min-Max控制器,NGPC控制器通过调节燃料量使转速波动超调量显著降低,且响应曲线平滑度提高42%;控制误差显著降低,转速与温度约束违规率为零,单步计算耗时7~9 ms,占控制周期的9%以内,满足重型燃气轮机实时控制要求。 展开更多
关键词 广义预测控制 重型燃气轮机 长短期记忆网络 非线性模型
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西部陆海新通道综合运输效率测算与时空演化分析
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作者 黄承锋 黄珏烽 雷洋 《商业经济研究》 北大核心 2026年第3期69-74,共6页
西部陆海新通道作为新时代国家重大战略工程,是推动区域协调发展、畅通国内国际双循环的重要基础设施。本文基于超效率EBM模型,结合2014-2023年数据,对沿线13个省份综合运输效率进行测算与时空演化分析。结果表明:综合运输效率整体从0.... 西部陆海新通道作为新时代国家重大战略工程,是推动区域协调发展、畅通国内国际双循环的重要基础设施。本文基于超效率EBM模型,结合2014-2023年数据,对沿线13个省份综合运输效率进行测算与时空演化分析。结果表明:综合运输效率整体从0.569提升至0.748,呈现“南高北低、核心强边缘弱”分布格局,广西、重庆等南部省份效率领先,而新疆、青海等北部及边缘地区效率偏低;动态演变呈现政策驱动下的“W”型趋势,2023年效率达历史高点,但区域差距仍然显著;空间分布上形成以成渝为核心的“高-高”集聚区,西北地区则集聚为“低-低”洼地,区域协同网络尚不完善。据此,提出基础设施均衡布局、跨区域联动机制完善、政策体系优化与空间协作深化等建议,为西部陆海新通道高质量发展提供实证支撑与理论参考。 展开更多
关键词 西部陆海新通道 综合运输效率 超效率EBM模型 时空演化 空间自相关
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基于深度强化学习的边缘协同配电网任务卸载博弈优化策略
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作者 谭传玉 王鹏 +3 位作者 林佳颖 秦四军 雷杨 尹靖元 《科学技术与工程》 北大核心 2026年第1期181-190,共10页
近年来,人工智能、分布式计算等技术极大推动了配电网运行性能的提升,但在任务计算、数据处理效率等方面仍面临巨大挑战。为此,提出一种基于深度强化学习(deep reinforcement learning, DRL)的边缘协同任务卸载博弈优化策略,以提升配电... 近年来,人工智能、分布式计算等技术极大推动了配电网运行性能的提升,但在任务计算、数据处理效率等方面仍面临巨大挑战。为此,提出一种基于深度强化学习(deep reinforcement learning, DRL)的边缘协同任务卸载博弈优化策略,以提升配电网任务执行效率和系统整体计算性能。首先,建立了考虑任务优先级的配电网边-边协同任务计算模型。进一步,将任务卸载问题建模为Stackelberg博弈。其中,本地服务器作为领导者,以优化任务执行时延和计算成本的综合性能为目标;目标卸载服务器作为跟随者,以提供计算服务获取最大收益为目标。然后,证明了博弈模型纳什均衡的存在性。最后,提出了基于多智能体深度确定性策略梯度(multi-agent deep deterministic policy gradient, MADDPG)的博弈模型求解方法。算例结果表明,与随机卸载和贪心卸载算法相比,所提方法下本地服务器效用值分别提高了66.7%和52.4%。任务的平均执行时间比随机卸载减少14.4%。同时,配电网各服务器的计算负荷分配更加均衡,平均负荷系数较随机卸载方法降低了11.9%。 展开更多
关键词 任务卸载 深度强化学习 边-边协同 STACKELBERG博弈 纳什均衡
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基于CatBoost-LR的区块链异常交易检测和可解释性研究
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作者 王珊 雷阳 林伟 《情报杂志》 北大核心 2026年第4期84-90,101,共8页
[目的]区块链异常交易给公民财产安全带来了巨大的风险。针对目前区块链异常交易召回率不高、结果可解释性不强等问题,提出基于CatBoost-LR的区块链异常交易检测模型,提高异常交易检测效果,并增强可解释性。[方法]首先,运用CatBoost算... [目的]区块链异常交易给公民财产安全带来了巨大的风险。针对目前区块链异常交易召回率不高、结果可解释性不强等问题,提出基于CatBoost-LR的区块链异常交易检测模型,提高异常交易检测效果,并增强可解释性。[方法]首先,运用CatBoost算法生成决策树,进行特征组合和离散化;其次,将新构造的特征运用在LR模型上,通过CatBoost与LR融合模型进行分类预测;最后,运用SHAP解释方法对实验结果进行归因,评估了特征对异常交易的影响强度及其作用机制。[结果/结论]模型预测结果召回率达到86.99%、F1值达到89.58%,地址之间的交易总次数、计算费用最小值和首次发送的区块高度等是预测区块链交易是否合法的重要特征,SHAP解释方法能够在保证机器学习预测模型精度的同时,提供清晰的解释性。 展开更多
关键词 区块链 异常交易检测 SHAP 逻辑回归 CatBoost
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面向石油化工难分离体系的分离技术研究进展
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作者 陈毓秋 潘婉莹 +3 位作者 闫佳淇 周嘉萍 雷杨 张香平 《化工学报》 北大核心 2026年第1期16-33,共18页
在石油化工中,分离过程是关键过程环节,且能耗占比大,其技术复杂度与效率直接决定了产品质量、能耗水平及环保性能。诸多难分离体系如芳烃与非芳烃、烯烃与烷烃等,因组分性质相近、易形成共沸物、近沸物等特性,给传统分离技术带来严峻... 在石油化工中,分离过程是关键过程环节,且能耗占比大,其技术复杂度与效率直接决定了产品质量、能耗水平及环保性能。诸多难分离体系如芳烃与非芳烃、烯烃与烷烃等,因组分性质相近、易形成共沸物、近沸物等特性,给传统分离技术带来严峻挑战。首先系统梳理和分析了石油化工难分离体系类型及特征,并详细介绍了精馏、萃取、结晶等传统分离技术方法的应用及其局限性,探讨了离子液体萃取精馏、膜分离及吸附等新型分离技术带来的分离流程创新和过程瓶颈。并提出了面向过程低碳化、绿色化要求的分离技术未来发展方向,以实现石油化工难分离体系的高效、节能、环保分离,推动石油化工行业低碳绿色可持续发展。 展开更多
关键词 传质 分离 优化设计 过程系统
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Bromodomain-containing protein 4 knockdown promotes neuronal ferroptosis in a mouse model of subarachnoid hemorrhage 被引量:2
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作者 Peng Lu Fan Zhang +8 位作者 lei yang Yijing He Xi Kong Kecheng Guo Yuke Xie Huangfan Xie Bingqing Xie Yong Jiang Jianhua Peng 《Neural Regeneration Research》 2026年第2期715-729,共15页
Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage.Neuronal ferroptosis in particular plays an important role in... Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage.Neuronal ferroptosis in particular plays an important role in early brain injury.Bromodomain-containing protein 4,a member of the bromo and extraterminal domain family of proteins,participated in multiple cell death pathways,but the mechanisms by which it regulates ferroptosis remain unclear.The primary aim of this study was to investigate how bromodomain-containing protein 4 affects neuronal ferroptosis following subarachnoid hemorrhage in vivo and in vitro.Our findings revealed that endogenous bromodomain-containing protein 4 co-localized with neurons,and its expression was decreased 48 hours after subarachnoid hemorrhage of the cerebral cortex in vivo.In addition,ferroptosis-related pathways were activated in vivo and in vitro after subarachnoid hemorrhage.Targeted inhibition of bromodomain-containing protein 4 in neurons increased lipid peroxidation and intracellular ferrous iron accumulation via ferritinophagy and ultimately led to neuronal ferroptosis.Using cleavage under targets and tagmentation analysis,we found that bromodomain-containing protein 4 enrichment in the Raf-1 promoter region decreased following oxyhemoglobin stimulation in vitro.Furthermore,treating bromodomain-containing protein 4-knockdown HT-22 cell lines with GW5074,a Raf-1 inhibitor,exacerbated neuronal ferroptosis by suppressing the Raf-1/ERK1/2 signaling pathway.Moreover,targeted inhibition of neuronal bromodomain-containing protein 4 exacerbated early and long-term neurological function deficits after subarachnoid hemorrhage.Our findings suggest that bromodomain-containing protein 4 may have neuroprotective effects after subarachnoid hemorrhage,and that inhibiting ferroptosis could help treat subarachnoid hemorrhage. 展开更多
关键词 bromodomain-containing protein 4 cell death early brain injury ferritinophagy ferroptosis neurological deficits neuron oxidative stress RAF proto-oncogene serine/threonine-protein kinase(Raf-1) subarachnoid hemorrhage
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基于System xc/GSH/GPX4信号通路探讨薏苡附子败酱散对UC模型大鼠肠上皮细胞铁死亡的影响
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作者 雷阳 朱超伦 +2 位作者 孟令飞 赵子旭 张双喜 《山东中医药大学学报》 2026年第2期181-189,共9页
目的:探讨薏苡附子败酱散调控胱氨酸-谷氨酸转运体系统/谷胱甘肽/谷胱甘肽过氧化物酶4(System xc/GSH/GPX4)信号通路对溃疡性结肠炎(UC)模型大鼠结肠组织铁死亡的影响。方法:60只SD大鼠随机分为模型组、薏苡附子败酱散组、美沙拉嗪组,每... 目的:探讨薏苡附子败酱散调控胱氨酸-谷氨酸转运体系统/谷胱甘肽/谷胱甘肽过氧化物酶4(System xc/GSH/GPX4)信号通路对溃疡性结肠炎(UC)模型大鼠结肠组织铁死亡的影响。方法:60只SD大鼠随机分为模型组、薏苡附子败酱散组、美沙拉嗪组,每组20只,采用三硝基苯磺酸(TNBS)/乙醇联合灌肠法诱导构建UC模型,另取20只大鼠作为空白组。自模型构建次日起,正常组、模型组给予生理盐水等体积灌胃,薏苡附子败酱散组(6.00 g/kg)及美沙拉嗪组(0.35 g/kg)给予相应药物灌胃,每日1次,连续给药14 d。每日记录大鼠体质量、粪便等一般情况;苏木素-伊红(HE)染色法观察结肠组织形态学变化;酶联免疫吸附测定(ELISA)法检测血清白细胞介素(IL)-1β、IL-10、IL-17含量;生化检测法检测结肠组织GSH含量;比色法检测结肠组织匀浆中Fe^(2+)水平;实时荧光-聚合酶链式反应(qRT-PCR)法检测大鼠结肠组织环氧化酶-2(PTGS2)、溶质载体家族7成员11(SLC7A11)、GPX4 mRNA表达水平;蛋白质印迹(WB)法检测结肠组织PTGS2、SLC7A11、GPX4蛋白表达水平。结果:与模型组比较,薏苡附子败酱散组大鼠体质量增加值上升(P<0.05),疾病活动指数(DAI)评分及结肠黏膜损伤指数(CMDI)评分降低(P<0.05);血清IL-1β、IL-17含量降低(P<0.05),IL-10含量升高(P<0.05),结肠组织病理性损伤明显减轻,GSH含量升高(P<0.05),结肠组织匀浆中Fe^(2+)水平降低(P<0.05),SLC7A11、GPX4 mRNA表达水平升高(P<0.05),PTGS2 mRNA表达水平下降(P<0.05),SLC7A11、GPX4蛋白表达量升高(P<0.05),PTGS2蛋白表达量下降(P<0.05)。结论:薏苡附子败酱散可能通过调节System xc/GSH/GPX4信号通路抑制结肠组织铁死亡,从而改善UC模型大鼠结肠黏膜损伤。 展开更多
关键词 薏苡附子败酱散 溃疡性结肠炎 铁死亡 胱氨酸-谷氨酸转运体系统 谷胱甘肽 谷胱甘肽过氧化物酶4
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运营铁路隧道衬砌内部缺陷快速普查试验研究
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作者 江波 雷洋 +2 位作者 赵玉才 王兆宁 贾飞宇 《铁道建筑》 北大核心 2026年第2期131-136,共6页
为实现运营铁路隧道衬砌内部缺陷的高效、无损、大规模普查,突破传统接触式地面耦合地质雷达检测速度慢、难以在有限天窗期内完成长大隧道群普查的技术瓶颈,本文提出并系统验证了一种基于车载空气耦合地质雷达的远距离(与衬砌表面悬空间... 为实现运营铁路隧道衬砌内部缺陷的高效、无损、大规模普查,突破传统接触式地面耦合地质雷达检测速度慢、难以在有限天窗期内完成长大隧道群普查的技术瓶颈,本文提出并系统验证了一种基于车载空气耦合地质雷达的远距离(与衬砌表面悬空间距1.0~4.0 m)快速检测方法。选取典型运营铁路隧道区段,采用中心频率300 MHz的车载空气耦合型地质雷达系统,以40~70 km/h的检测速度进行快速普查。为验证其筛查可靠性,利用中心频率900 MHz的地耦地质雷达对空耦地质雷达识别的异常区段进行精细复核与对比分析。结果表明:车载空耦地质雷达与地耦地质雷达在缺陷的位置、范围、形态及发展趋势上均表现出高度一致性;车载空耦地质雷达系统能有效识别衬砌内部浅层的严重缺陷,检测速度可达70 km/h,且不占用维修天窗、不影响正常行车。本文验证了空耦地质雷达用于快速筛查的可行性,为构建“空耦地质雷达快速筛查+地耦地质雷达精细详查”的分级协同检测体系提供了关键技术支撑与实证依据,具有显著的工程应用与推广价值。 展开更多
关键词 隧道工程 衬砌缺陷 地质雷达 空气耦合 快速普查 分级检测
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大型热挤压模具失效形式及表面增强延寿技术
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作者 雷杨 孟可可 +4 位作者 秦瑞廷 林莺莺 朱贝贝 孟丽 曾晓雁 《锻压技术》 北大核心 2026年第3期1-10,共10页
大型热挤压模具尺寸大、制造难、成本高,延长模具服役寿命对降低大型零件的挤压制造成本、提升产品竞争能力具有重要作用。围绕大型热挤压模具延寿技术,归纳总结了大型热挤压模具的失效形式和可借鉴的热成形模具表面强化技术,分析了大... 大型热挤压模具尺寸大、制造难、成本高,延长模具服役寿命对降低大型零件的挤压制造成本、提升产品竞争能力具有重要作用。围绕大型热挤压模具延寿技术,归纳总结了大型热挤压模具的失效形式和可借鉴的热成形模具表面强化技术,分析了大型高效激光熔覆技术的研究现状和技术发展趋势。在此基础上,重点分析了激光熔覆表面强化技术相较于其他表面强化方法的优势以及熔覆材料、熔覆工艺和熔覆装备等方面的研究进展,明确了利用激光熔覆技术解决大型热挤压模具表面强化难题需进一步解决的技术问题,为延长大型热挤压模具服役寿命提供了技术路径。 展开更多
关键词 大型热挤压模具 表面强化 模具延寿 激光熔覆 热疲劳 热磨损
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基于对抗神经网络的农业机械GPS数据异常检测
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作者 雷杨 李倩文 +1 位作者 姬翔 赵凯旋 《农机化研究》 北大核心 2026年第6期188-195,共8页
农业机械依靠GPS数据进行自动驾驶控制和路径规划,然而由于应用环境的复杂性,GPS数据可能会出现异常,导致自动驾驶控制不准确,甚至引发事故。针对上述问题,提出了一种基于生成对抗网络(GAN)的异常检测模型—LK-GAN,用于识别农业机械作... 农业机械依靠GPS数据进行自动驾驶控制和路径规划,然而由于应用环境的复杂性,GPS数据可能会出现异常,导致自动驾驶控制不准确,甚至引发事故。针对上述问题,提出了一种基于生成对抗网络(GAN)的异常检测模型—LK-GAN,用于识别农业机械作业时的GPS异常。该模型结合了Kolmogorov-Arnold网络(KAN)和长短期记忆网络(LSTM),借助KAN的非线性表达能力来提升LSTM在时间序列建模中的性能。另外,还提出了一种生成损失计算方法,通过平衡生成器和判别器的训练,在提高模型收敛性的同时提升异常检测的准确性。在数据集上的试验结果表明:LK-GAN在精度、召回率和F1分数方面优于大多数模型,在GPS数据集中精确率和召回率分别达到93.17%和92.27%。该研究可有效提高农机作业过程中GPS数据的准确性,为智能农机在复杂环境中的稳定运行和作业精度管理提供了保障。 展开更多
关键词 农业机械 GPS数据异常检测 对抗神经网络 数据挖掘技术 深度学习
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The Relationship between Parental Marital Conflict and Adolescent Short Video Dependence:A Chain Mediation Model
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作者 lei yang yang Liu 《International Journal of Mental Health Promotion》 2026年第1期168-186,共19页
Background:This study aims to investigate the underlying mechanisms between parental marital conflict and adolescent short video dependence by constructing a chain mediation model,focusing on the mediating roles of ex... Background:This study aims to investigate the underlying mechanisms between parental marital conflict and adolescent short video dependence by constructing a chain mediation model,focusing on the mediating roles of experiential avoidance and emotional disturbance(anxiety,depression,and stress).Methods:Conducted in January 2025,the research recruited 4125 adolescents from multiple Chinese provinces through convenience sampling;after data cleaning,3957 valid participants(1959 males,1998 females)were included.Using a cross-sectional design,measures included parental marital conflict,experiential avoidance,anxiety,depression,stress,and short video dependence.Results:Pearson correlation analysis revealed significant positive correlations among all variables.Mediation analysis using the SPSS PROCESS macro showed that parental marital conflict directly predicted short video dependence(β=0.269,p<0.001),and also significantly predicted experiential avoidance(β=0.519,p<0.001),anxiety(β=0.072,p<0.001),depression(β=0.067,p<0.001),and stress(β=0.048,p<0.05).Experiential avoidance further predicted anxiety(β=0.521,p<0.001),depression(β=0.489,p<0.001),stress(β=0.408,p<0.001),and short video dependence(β=0.244,p<0.001).While both anxiety(β=0.050,p<0.05)and depression(β=0.116,p<0.001)positively predicted short video dependence,stress did not(β=0.019,p=0.257).Overall,experiential avoidance,anxiety,depression,and stress significantly mediated the relationship between parental marital conflict and short video dependence.Conclusion:These findings confirm that parental marital conflict not only directly influences adolescent short video dependence but also operates through a chain mediation pathway involving experiential avoidance and emotional disturbance,highlighting central psychological mechanisms and providing theoretical support for integrated mental health and behavioral interventions. 展开更多
关键词 Parental marital conflict experiential avoidance ANXIETY depression stress emotional disturbance short video dependence
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Myostatin promotes proliferation of bovine muscle satellite cells through activating TRPC4/Ca^(2+)/calcineurin/NFATc3 pathway
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作者 Yajie Gao Song Wang +12 位作者 Anqi Di Chao Hai Di Wu Zhenting Hao Lige Bu Xuefei Liu Chunling Bai Guanghua Su Lishuang Song Zhuying Wei Zhonghua Liu lei yang Guangpeng Li 《Journal of Integrative Agriculture》 2026年第3期1125-1136,共12页
Myostatin(MSTN)is principally expressed in skeletal muscle and negatively regulates muscle growth and development.MSTN mutation can induce muscle overgrowth in cattle by activating cell proliferation,presenting a“dou... Myostatin(MSTN)is principally expressed in skeletal muscle and negatively regulates muscle growth and development.MSTN mutation can induce muscle overgrowth in cattle by activating cell proliferation,presenting a“double-muscle”phenotype.However,the specific regulatory mechanism is still unclear.Here,we found that Ca^(2+)content in muscle tissue and muscle satellite cells of MSTN mutated(MSTN^(–/–))cattle were significantly increased compared to wild-type(WT).Furthermore,transcriptome analysis of muscle satellite cells revealed that TRPC4 was significantly increased in MSTN^(–/–)cattle.And the expression of TRPC4 in muscle tissue of MSTN^(–/–)cattle was detected by RT-qPCR and Western blot,which was significantly higher than that of WT.These results suggested that MSTN mutation promoted muscle satellite cells proliferation through activation of TRPC4 channel.To further verify,ML204,a specific inhibitor of TRPC4,was used to treat MSTN^(–/–)muscle satellite cells.We found that cell proliferation was inhibited,calcineurin expression was downregulated,and the entry of NFATc3 into nuclei was reduced,which was similar to WT group.Thus,MSTN mutation leads to the activation of TRPC4 channel,which increases intracellular Ca^(2+)content,further activates calcineurin/NFATc3 pathway,and ultimately promotes the proliferation of muscle satellite cells. 展开更多
关键词 MYOSTATIN cell proliferation CA^(2+) TRPC4 NFATc3
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化学发光:炫彩实验探秘
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作者 张文骞 杨智 +2 位作者 吴顺香 杨磊 顾榜 《大学化学》 2026年第3期307-321,共15页
从夜空星光到城市灯光,发光现象在生活中俯拾皆是,在各种发光现象背后,蕴藏着丰富的化学反应原理。化学发光作为一种特殊发光形式,与传统的热发光有别,它是化学反应过程中产生的能量以光的形式释放出来的现象。鲁米诺因结构简、合成易... 从夜空星光到城市灯光,发光现象在生活中俯拾皆是,在各种发光现象背后,蕴藏着丰富的化学反应原理。化学发光作为一种特殊发光形式,与传统的热发光有别,它是化学反应过程中产生的能量以光的形式释放出来的现象。鲁米诺因结构简、合成易、水溶性优且发光量子效率高,常被用于液相化学发光试剂。双草酸酯具有化学稳定性强、发光性能优、安全性高、环保性好的特点,是一种优良的发光材料。本文以科学普及为鹄的,设计开展了一系列生动的化学实验,展现鲁米诺和双草酸酯的化学发光特性,探讨其在不同环境下的应用潜力,并借助简单的实验现象向大众呈现化学发光之趣。实验包括蓝绿光交汇的发光喷泉、模拟犯罪现场血迹的检验、光影流转的充气葫芦、墨韵生辉的发光毛笔以及黑暗中的蓝色玫瑰。通过这些趣美的科普实验,直观地展示了化学发光现象,进一步探讨了其在实际应用中的可行性,彰显化学之精妙。 展开更多
关键词 鲁米诺 双草酸酯 化学科普 趣味性 互动性
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Convective Mode of Tornadic Storms in Northeastern China:A Preliminary Study
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作者 Chao YUAN Ying WANG +3 位作者 lei yang Fan PING Jing MIAO Yingcong ZHENG 《Advances in Atmospheric Sciences》 2026年第1期170-190,共21页
This study presents a comprehensive analysis of 132 tornadic events in northeastern China from 2004 to 2023,utilizing radar and ERA5 reanalysis data to investigate the climatology,environmental drivers,and synoptic li... This study presents a comprehensive analysis of 132 tornadic events in northeastern China from 2004 to 2023,utilizing radar and ERA5 reanalysis data to investigate the climatology,environmental drivers,and synoptic linkages with Northeast China cold vortices(NCCVs)of tornadic storms under different convective modes.Results reveal that discrete storms account for 70%of events,with clustered cells(CC)being the most frequent mode,while significant tornadoes(EF2+)are primarily associated with isolated cells(IC)and broken lines(BL).The storm mode distribution in northeastern China resembles that of the central United States but with a higher proportion of CC and lower IC.In contrast,southern China exhibits a higher frequency of quasi-linear(QL)modes(>50%),similar to European patterns.Although no single parameter clearly differentiates between all tornado modes,distinct morphological characteristics emerge through specific parameter combinations:NL modes are characterized by high 0-1 km storm-relative helicity(SRH1)and humidity but low 0-6 km shear(SR6),whereas IC modes display contrasting features with low SRH1 and high CAPE.Notably,83%of tornadoes are associated with NCCVs,preferentially forming in southeastern/southwestern quadrants.Strong tornadoes favor southeastern quadrants,while NCCV intensity correlates with tornadic distance from vortex centers.Three characteristic synoptic configurations emerge:(T1)strong deep vortices with vertically aligned cold troughs,generating southeast-dominant tornado clusters characterized by a high proportion of BL and QL modes;(T2)weaker vortices featuring sub-synoptic troughs,with southern-distributed events dominated by a predominance of the CC mode;(T3)transverse-trough systems exhibiting CAPE-SRH decoupling and reduced tornadic activity.This study enhances our understanding of tornadoes in northeastern China,informing future research on formation mechanisms,prediction methods,and disaster prevention strategies. 展开更多
关键词 convective storms northeastern China TORNADOES MORPHOLOGY northeastern China cold vortex
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ROS-sensitive dihydroartemisinin prodrug amplify chemo-immunotherapy efficacy of doxorubicin by coordinating robust tumor cell immunogenic cell death and PD-L1 blockade
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作者 Xiaopeng Han Jiayin Li +7 位作者 Fei Li Zhongyue Yuan Hao Li lei yang Yan-Ming Xia Chao Teng Chao Qin Lifang Yin 《Chinese Chemical Letters》 2026年第2期357-362,共6页
Doxorubicin(DOX)is known to elicit potent antitumor immune responses through the induction of immunogenic cell death(ICD).However,its therapeutic efficacy is undermined by the adaptive upregulation of programmed cell ... Doxorubicin(DOX)is known to elicit potent antitumor immune responses through the induction of immunogenic cell death(ICD).However,its therapeutic efficacy is undermined by the adaptive upregulation of programmed cell death ligand 1(PD-L1),which hijacked the antitumor immunity.In this study,we developed a reactive oxygen species(ROS)-responsive dihydroartemisinin(DHA)prodrug to facilitate the delivery of DOX via hydrophobic and electrostatic interactions.Upon internalization by tumor cells,the nanoparticles(NPs)preferentially accumulated in endoplasmic reticulum(ER),exacerbating ER stress and amplifying ICD to enhance tumor immunogenicity.Simultaneously,the oxidative intracellular environment trigged the degradation of NPs,releasing DHA,which downregulated PD-L1 by disrupting signal transducer and activator of transcription 3(STAT3)phosphorylation and inactivating the nuclear factor kappa-B(NF-κB)pathway.Consequently,the effective PD-L1 blockade and robust ICD response,synergistically inhibited breast cancer progression,significantly enhancing the chemo-immunotherapy efficacy of doxorubicin. 展开更多
关键词 ROS-sensitive-prodrug Dihydroartemisinin DOXORUBICIN CHEMO-IMMUNOTHERAPY Immunogenic cell death PD-L1 blockade
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Calculation of Viewing and Solar Geometry Angles for the Fengyun-4B Geostationary Satellite
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作者 Dazhi yang Yuhang MA +2 位作者 Yun CAO lei yang Hai ZHANG 《Advances in Atmospheric Sciences》 2026年第4期736-743,共8页
The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary sate... The calculation of viewing and solar geometry angles is a critical first step in retrieving atmospheric and surface variables from geostationary satellite observations.Whereas the viewing angles for geostationary satellites are not timevarying,a primary source of inaccuracy in solar positioning is the use of a single timestamp.Since pixel scanning times can differ significantly across the field-of-view disk(e.g.,by approximately 13 min for Fengyun-4B),this practice leads to errors of up to±2°in solar zenith angle,which translates to±50 W m^(−2) in extraterrestrial irradiance;the errors in solar azimuth angle can exceed±100°.Beyond scanning time,this work also quantifies the impact of other inputs—including altitude,surface pressure,air temperature,difference between Terrestrial Time and Universal Time,and atmospheric refraction—on the resulting angles.A comparison of our precise calculations with the official National Satellite Meteorological Center L1_GEO product shows an accuracy within 0.1°,confirming its utility for most retrieval tasks.To facilitate higher precision when required,this work releases the corresponding satellite and solar positioning codes in both R and Python. 展开更多
关键词 Fengyun-4B viewing and solar geometry solar position algorithm geostationary satellite code availability
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Porcine decellularized nerve matrix hydrogel attenuates neuroinflammation after peripheral nerve injury by inhibiting the TLR4/MyD88/NF-κB axis
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作者 Rui Li Jianquan Liu +7 位作者 Liuxun Li Guotian Luo Xinrong Yuan Shichao Shen Yongpeng Shi Jianlong Wu Bin Yan lei yang 《Neural Regeneration Research》 2026年第3期1222-1235,共14页
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop... Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury. 展开更多
关键词 anti-inflammatory reaction macrophage polarization NEUROINFLAMMATION peripheral nerve injury porcine decellularized nerve matrix hydrogel
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白及活性成分及质量控制研究进展
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作者 门宛霞 雷阳 唐开城 《成都大学学报(自然科学版)》 2026年第1期1-6,共6页
白及富含菲类、联苄类和有机酸类等化合物,具有止血、促进创伤愈合、保护黏膜及美白抗衰老等药理作用,在中医药和现代医疗领域广泛应用.然而,当前针对白及的质量控制研究仍存在局限性,现有质量控制指标难以系统表征其整体质量属性,制约... 白及富含菲类、联苄类和有机酸类等化合物,具有止血、促进创伤愈合、保护黏膜及美白抗衰老等药理作用,在中医药和现代医疗领域广泛应用.然而,当前针对白及的质量控制研究仍存在局限性,现有质量控制指标难以系统表征其整体质量属性,制约了药材标准化进程.系统地梳理白及相关活性成分及质量控制研究进展,以期为后续深入研究白及的药用价值、开发创新药物及制定更完善的质量标准提供参考. 展开更多
关键词 白及 活性成分 质量控制 研究进展
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