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A Biomimetic Stress Field Modulation Strategy Inspired by Scorpion Compound Slit Sensilla Enabled High-Accuracy and Low-Power Positioning Sensor for Identifying the Load Incident Angles
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作者 Junqiu Zhang Yu Chen +11 位作者 Haoran Li Jiqi Gao Xiangbo Gu Jiachao Wu Xiaojing Qin Kejun Wang Bin Zhu Daobing Chen Tao Sun Jianhua Fan Zhiwu Han Luquan Ren 《Journal of Bionic Engineering》 2025年第2期727-738,共12页
Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rat... Numerous arthropods evolve and optimize sensory systems, enabling them to effectively adapt complex and competitive habitats. Typically, scorpions can precisely perceive the prey location with the lowest metabolic rate among invertebrates. This biological phenomenon contrasts sharply with engineered systems, which generally associates high accuracy with substantial energy consumption. Inspired by the Scorpion Compound Slit Sensilla (SCSS) with a stress field modulation strategy, a bionic positioning sensor with superior precision and minimal power consumption is developed for the first time, which utilizes the particular Minimum Positioning Units (MPUs) to efficiently locate vibration signals. The single MPU of the SCSS can recognize the direction of collinear loads by regulating the stress field distribution and further, the coupling action of three MPUs can realize all-angle vibration monitoring in plane. Experiments demonstrate that the bionic positioning sensor achieves 1.43 degrees of angle-error-free accuracy without additional energy supply. As a proof of concept, two bionic positioning sensors and machine learning algorithm are integrated to provide centimeter (cm)-accuracy target localization, ideally suited for the man-machine interaction. The novel design offers a new mechanism for the design of traditional positioning devices, improving precision and efficiency in both the meta-universe and real-world Internet-connected systems. 展开更多
关键词 Scorpion compound Slit Sensilla(SCSS) Vibration Source Stress Field modulation Strategy High-accuracy and low-power Positioning Sensor Minimum Positioning Unit(MPU)
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MDGET-MER:Multi-Level Dynamic Gating and Emotion Transfer for Multi-Modal Emotion Recognition
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作者 Musheng Chen Qiang Wen +2 位作者 Xiaohong Qiu Junhua Wu Wenqing Fu 《Computers, Materials & Continua》 2026年第3期872-893,共22页
In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing method... In multi-modal emotion recognition,excessive reliance on historical context often impedes the detection of emotional shifts,while modality heterogeneity and unimodal noise limit recognition performance.Existing methods struggle to dynamically adjust cross-modal complementary strength to optimize fusion quality and lack effective mechanisms to model the dynamic evolution of emotions.To address these issues,we propose a multi-level dynamic gating and emotion transfer framework for multi-modal emotion recognition.A dynamic gating mechanism is applied across unimodal encoding,cross-modal alignment,and emotion transfer modeling,substantially improving noise robustness and feature alignment.First,we construct a unimodal encoder based on gated recurrent units and feature-selection gating to suppress intra-modal noise and enhance contextual representation.Second,we design a gated-attention crossmodal encoder that dynamically calibrates the complementary contributions of visual and audio modalities to the dominant textual features and eliminates redundant information.Finally,we introduce a gated enhanced emotion transfer module that explicitly models the temporal dependence of emotional evolution in dialogues via transfer gating and optimizes continuity modeling with a comparative learning loss.Experimental results demonstrate that the proposed method outperforms state-of-the-art models on the public MELD and IEMOCAP datasets. 展开更多
关键词 multi-modal emotion recognition dynamic gating emotion transfer module cross-modal dynamic alignment noise robustness
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Protein synthesis modulation as a therapeutic approach for amyotrophic lateral sclerosis and frontotemporal dementia 被引量:4
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作者 Santiago E.Charif M.Florencia Vassallu +1 位作者 Lara Salvañal Lionel M.Igaz 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第7期1423-1430,共8页
Protein synthesis is essential for cells to perform life metabolic processes.Pathological alterations of protein content can lead to particular diseases.Cells have an intrinsic array of mechanisms and pathways that ar... Protein synthesis is essential for cells to perform life metabolic processes.Pathological alterations of protein content can lead to particular diseases.Cells have an intrinsic array of mechanisms and pathways that are activated when protein misfolding,accumulation,aggregation or mislocalization occur.Some of them(like the unfolded protein response)represent complex interactions between endoplasmic reticulum sensors and elongation factors that tend to increase expression of chaperone proteins and/or repress translation in order to restore protein homeostasis(also known as proteostasis).This is even more important in neurons,as they are very susceptible to harmful effects associated with protein overload and proteostatic mechanisms are less effective with age.Several neurodegenerative pathologies such as Alzheimer’s,Parkinson’s,and Huntington’s diseases,amyotrophic lateral sclerosis and frontotemporal dementia exhibit a particular molecular signature of distinct,unbalanced protein overload.In amyotrophic lateral sclerosis and frontotemporal dementia,the majority of cases present intracellular inclusions of ubiquitinated transactive response DNA-binding protein of 43 kDa(TDP-43).TDP-43 is an RNA binding protein that participates in RNA metabolism,among other functions.Dysregulation of TDP-43(e.g.aggregation and mislocalization)can dramatically affect neurons,and this has been linked to disease development.Expression of amyotrophic lateral sclerosis/frontotemporal dementia TDP-43-related mutations in cellular and animal models has been shown to recapitulate key features of the amyotrophic lateral sclerosis/frontotemporal dementia disease spectrum.These variants can be causative of degeneration onset and progression.Most neurodegenerative diseases(including amyotrophic lateral sclerosis and frontotemporal dementia)have no cure at the moment;however,modulating translation has recently emerged as an attractive approach that can be performed at several steps(i.e.regulating activation of initiation and elongation factors,inhibiting unfolded protein response activation or inducing chaperone expression and activity).This review focuses on the features of protein imbalance in neurodegenerative disorders and the relevance of developing therapeutical compounds aiming at restoring proteostasis.We strive to highlight the importance of research on drugs that,not only restore protein imbalance without compromising translational activity of cells,but are also as safe as possible for the patients. 展开更多
关键词 amyotrophic lateral sclerosis frontotemporal dementia NEURODEGENERATION neurodegenerative diseases protein imbalance protein synthesis modulation PROTEOSTASIS therapeutical compounds transactive response DNA-binding protein of 43 kDa TRANSLATION unfolded protein response
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Unsupervised multi-modal image translation based on the squeeze-and-excitation mechanism and feature attention module 被引量:1
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作者 胡振涛 HU Chonghao +1 位作者 YANG Haoran SHUAI Weiwei 《High Technology Letters》 EI CAS 2024年第1期23-30,共8页
The unsupervised multi-modal image translation is an emerging domain of computer vision whose goal is to transform an image from the source domain into many diverse styles in the target domain.However,the multi-genera... The unsupervised multi-modal image translation is an emerging domain of computer vision whose goal is to transform an image from the source domain into many diverse styles in the target domain.However,the multi-generator mechanism is employed among the advanced approaches available to model different domain mappings,which results in inefficient training of neural networks and pattern collapse,leading to inefficient generation of image diversity.To address this issue,this paper introduces a multi-modal unsupervised image translation framework that uses a generator to perform multi-modal image translation.Specifically,firstly,the domain code is introduced in this paper to explicitly control the different generation tasks.Secondly,this paper brings in the squeeze-and-excitation(SE)mechanism and feature attention(FA)module.Finally,the model integrates multiple optimization objectives to ensure efficient multi-modal translation.This paper performs qualitative and quantitative experiments on multiple non-paired benchmark image translation datasets while demonstrating the benefits of the proposed method over existing technologies.Overall,experimental results have shown that the proposed method is versatile and scalable. 展开更多
关键词 multi-modal image translation generative adversarial network(GAN) squeezeand-excitation(SE)mechanism feature attention(FA)module
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热脱附-气流调制全二维气相色谱-飞行时间质谱测定环境大气中中等挥发性有机物
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作者 汪睿 李英杰 +2 位作者 王佳华 马长文 蒋家奎 《色谱》 北大核心 2026年第4期453-466,共14页
环境大气中中等挥发性有机物(IVOCs)组成复杂;因受传统一维气相色谱柱分离能力限制,大部分IVOCs以未分离的色谱峰从色谱柱流出洗脱,因此无法将IVOCs准确识别和定量,制约了对其准确溯源。针对以上问题,本研究基于热脱附-气流调制全二维... 环境大气中中等挥发性有机物(IVOCs)组成复杂;因受传统一维气相色谱柱分离能力限制,大部分IVOCs以未分离的色谱峰从色谱柱流出洗脱,因此无法将IVOCs准确识别和定量,制约了对其准确溯源。针对以上问题,本研究基于热脱附-气流调制全二维气相色谱-飞行时间质谱(TD-FM GC×GC-TOF MS)技术,通过优化气流调制周期的填充时间和吹扫时间,建立了一种高效分离和定量环境大气中IVOCs的分析方法。以ZB-5HT(20 m×0.18 mm×0.18μm)为一维色谱柱、BP-50(5 m×0.25 mm×0.20μm)为二维色谱柱分离IVOCs,设置填充时间2870 ms、吹扫时间130 ms。在优化的分析条件下,69个定量目标物在1~20 ng/管范围内呈现良好的线性关系,相关系数为0.9223~0.9984等;方法检出限为0.0107~0.4101 ng/m^(3);目标物在1 ng/管加标水平下的回收率为80.4%~136.0%,在1、3和10 ng/管的相对标准偏差分别为4.5%~33.9%、3.2%~19.9%、3.5%~18.6%。利用该方法测定上海城区环境大气中IVOCs的质量浓度和组成分布,结果显示,总IVOCs质量浓度在8.6~61.1μg/m^(3),样品中检测到可识别有机物853个,对总IVOCs质量浓度贡献可高达96.2%,且新识别的芳香烃、Cl-IVOCs、O-IVOCs等有机物与常规监测目标物表现出不同排放来源特征。因此,该方法不仅为测定环境大气复杂IVOCs提供了一种可靠的技术手段,也为大气中IVOCs的精准溯源提供了数据支撑,还可应用于其他环境介质中IVOCs的测定,为多介质中IVOCs污染特征研究提供有力的技术支持。 展开更多
关键词 热脱附 气流调制 全二维气相色谱 飞行时间质谱 中等挥发性有机物 环境大气
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矿化物增强木塑复合材料研究进展
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作者 胡建鹏 宋冠霖 《塑料科技》 北大核心 2026年第2期190-195,共6页
矿化物凭借其优异的耐老化性、阻燃性及力学性能等特点,已成为重要的化工原料。以矿化物增强的复合材料因其环境友好特性、资源集约化利用潜力及优异的综合性能,已成为新型功能复合材料和绿色建筑材料领域的研究热点。文章从矿化物增强... 矿化物凭借其优异的耐老化性、阻燃性及力学性能等特点,已成为重要的化工原料。以矿化物增强的复合材料因其环境友好特性、资源集约化利用潜力及优异的综合性能,已成为新型功能复合材料和绿色建筑材料领域的研究热点。文章从矿化物增强体种类、矿化物与基体材料的复合方式以及复合材料功能拓展性方面系统阐述矿化物增强木塑复合材料(WPC)在力学性能、耐老化性、耐水性及阻燃性等方面的研究进展与现状。针对矿化物增强复合材料在矿物种类开发、矿化物与木塑基体间的界面调控、复合材料功能性拓展等方面存在的问题,展望矿化物增强WPC的发展趋势与应用前景,旨在为该材料的进一步研发提供依据。 展开更多
关键词 矿化物 木塑复合材料 性能调控 仿生矿化 功能化拓展
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Vanadium-based polyanionic compounds as cathode materials for sodium-ion batteries:Toward high-energy and high-power applications 被引量:7
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作者 Zhiqiang Lv Moxiang Ling +4 位作者 Meng Yue Xianfeng Li Mingming Song Qjong Zheng Huamin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期361-390,共30页
Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of lo... Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of low energy&power density and short cycling lifespan owing to the heavy mass and large radius of Na^(+).Vanadium-based polyanionic compounds have advantageous characteristic of high operating voltage,high ionic conductivity and robust structural framework,which is conducive to their high energy&power density and long lifespan for SIBs.In this review,we will overview the latest V-based polyanionic compounds,along with the respective characteristic from the intrinsic crystal structure to performance presentation and improvement for SIBs.One of the most important aspect is to discover the essential problems existed in the present V-based polyanionic compounds for high-energy&power applications,and point out most suitable solutions from the crystal structure modulation,interface tailoring and electrode configuration design.Moreover,some scientific issues of V-based polyanionic compounds shall be also proposed and related future direction shall be provided.We believe that this review can serve as a motivation for further development of novel V-based polyanionic compounds and drive them toward high energy&power applications in the near future. 展开更多
关键词 Sodium ion battery Vanadium-based polyanionic compounds High-energy&high-power applications Crystal structure modulation Interface tailoring Electrode configuration design
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Weakly-coupled mode division multiplexing over conventional multi-mode fiber with intensity modulation and direct detection 被引量:1
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作者 Juhao LI Zhongying WU +7 位作者 Dawei GE Jinglong ZHU Yu TIAN Yichi ZHANG Jinyi YU Zhengbin LI Zhangyuan CHEN Yongqi HE 《Frontiers of Optoelectronics》 EI CSCD 2019年第1期31-40,共10页
Multi-mode fiber(MMF)links are expected to greatly enhance capacity to cope with rapidly increasing data traffic in optical short-reach systems and networks.Recently,mode division multiplexing(MDM)over MMF has been pr... Multi-mode fiber(MMF)links are expected to greatly enhance capacity to cope with rapidly increasing data traffic in optical short-reach systems and networks.Recently,mode division multiplexing(MDM)over MMF has been proposed,in which different modes in MMF are utilized as spatial channels for data transmission.Stronglycoupled MDM techniques utilizing coherent detection and multiplex-input-multiplex-output(MIMO)digital signal processing(DSP)are complex and expensive for shortreach transmission.So the weakly-coupled approach by significantly suppressing mode coupling in the fiber and optical components has been proposed.In this way,the signals in each mode can be independently transmitted and received using conventional intensity modulation and direct detection(IM-DD).In this paper,we elaborate the key technologies to realize weakly-coupled MDM transmission over conventional MMF,including mode characteristic in MMF and weakly-coupled mode multiplexer/ demultiplexer(MUX/DEMUX).We also present the upto-date experimental results for weakly-coupled MDM transmission over conventional OM3 MMF.We show that weakly-coupled MDM scheme is promising for high-speed optical interconnections and bandwidth upgrade of already-deployed MMF links. 展开更多
关键词 multi-mode FIBER (MMF) MODE DIVISION MULTIPLEXING (MDM) weak MODE coupling intensity modulation and direct detection (IM-DD)
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Modulating the coordination microenvironment of uranyl compounds to enhance photocatalytic CO_(2)reduction
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作者 Zhi-Wei Huang Shu-Wen An +8 位作者 Kong-Qiu Hu Xiao-Bo Li Zhi-Ni Bin Zhi-Heng Zhou Lei Mei Zhi-Jun Guo Wang-Suo Wu Zhi-Fang Chai Wei-Qun Shi 《Inorganic Chemistry Frontiers》 2023年第16期4754-4762,共9页
Rationalizing the use of depleted uranium resources has always been of great interest.Herein,we have obtained two actinide compounds by regulating the ratio of each component in the crystal growth process.By modulatin... Rationalizing the use of depleted uranium resources has always been of great interest.Herein,we have obtained two actinide compounds by regulating the ratio of each component in the crystal growth process.By modulating the coordination microenvironment of uranyl,the actinide compounds exhibited significant differences in photocatalytic CO_(2)reduction performance.The photocatalytic CO_(2)reduction by UCu2 exhibited excellent reactivity,and the CO generation rate reached 481.6μmol g^(−1)h^(−1).This study provides a reference and support for the rational application of depleted uranium resources and the application of coordinated polymers in the field of photocatalytic CO_(2)reduction. 展开更多
关键词 depleted uranium resources photocatalytic CO reduction actinide compounds crystal growth processby coordination microenvironment rationalizing use depleted uranium resources uranyl compounds modulating coordination microenvironment
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基于VMD、PTSMFE与GWO-SVM的直流充电桩电源模块故障诊断方法研究 被引量:1
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作者 刘志峰 蒋浩 +1 位作者 刘贺 李新宇 《中国测试》 北大核心 2025年第8期87-97,共11页
为有效实施直流充电桩电源模块的回收再利用,必须克服故障诊断中串并联开关器件特征提取困难和故障定位不准确的难题。为此,提出变分模态分解(variational modal decomposition, VMD)、相位复合时移多尺度模糊熵(phase compound time-sh... 为有效实施直流充电桩电源模块的回收再利用,必须克服故障诊断中串并联开关器件特征提取困难和故障定位不准确的难题。为此,提出变分模态分解(variational modal decomposition, VMD)、相位复合时移多尺度模糊熵(phase compound time-shift multiscale fuzzy entropy, PTSMFE)和灰狼优化算法优化支持向量机分类器(gray wolf optimization algorithm-support vector machine classifier, GWO-SVM)的充电桩故障诊断方法。首先将采集的原始故障信号分解成多组本征模态函数(intrinsic mode function, IMF),再利用PTSMFE提取出故障信号的原始相位信息,并转化成相位系数后加入熵值中,得到各故障状态的特征向量。最后将特征向量输入GWO-SVM进行故障识别分类。实验结果表明:与常用的小波分析(wavelet analysis)特征提取和BP(back propagation)神经网络故障诊断方法进行对比,该文方法展现出准确性与高效性,分类识别准确率达到97.27%。 展开更多
关键词 直流充电桩电源模块 故障诊断 回收再利用 相位复合时移多尺度模糊熵
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5米S-SAR卫星固态有源馈电网络设计与实现
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作者 赵海洋 吕慎刚 +2 位作者 李阳斌 刘洪斌 郑新 《航天器工程》 北大核心 2025年第3期103-110,共8页
针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、... 针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、波束控制单元等来实现射频大功率有源馈电和多极化工作模式。通过对氮化镓(GaN)化合物半导体高功率器件的应用,实现了馈电系统的高功率、高效率和高可靠性等性能指标要求。通过机热一体化设计,形成了一种具有良好力学性能和热学性能的固态有源馈电网络系统。项目完成了规定的环境试验考核,并提交5米S-SAR卫星装星应用验证,结果表明:该固态有源馈电网络满足卫星的使用要求。 展开更多
关键词 5米S频段合成孔径雷达卫星 固态有源馈电网络 T/R组件 氮化镓化合物半导体
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基于MDL-U2-Net的盆底超声图像轻量级分割及参数测量
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作者 刘孝保 甘博敏 +1 位作者 姚廷强 申吉泓 《计算机辅助设计与图形学学报》 北大核心 2025年第2期277-292,共16页
准确地分割超声图像中盆底区域,是实现盆底疾病计算机辅助诊断的重要环节.针对盆底形态复杂、边界模糊、分割算法参数量庞大以及参数测量精度有限等问题,搭建了一种轻量级语义分割网络MDL-U2-Net并提出修补算法AC-F.首先,对基准U2-Net... 准确地分割超声图像中盆底区域,是实现盆底疾病计算机辅助诊断的重要环节.针对盆底形态复杂、边界模糊、分割算法参数量庞大以及参数测量精度有限等问题,搭建了一种轻量级语义分割网络MDL-U2-Net并提出修补算法AC-F.首先,对基准U2-Net进行结构优化和通道数调整,以有效地降低模型参数量;其次,融入复合损失函数以缓解训练损失波动并提升边界保持能力,提高网络对模糊边界的分割准确性;之后,提出深度非对称多尺度混洗卷积模块,以捕获特征空间采样的位置偏移信息,弥补轻量网络感受野不足和特征提取能力较弱的缺陷,提高网络对盆底复杂形态的建模能力;最后,采用修补算法对分割盆底进行精细化填补,以提高盆底完整性和参数测量的精度.在自制数据集上的实验结果表明,MDL-U2-Net对盆底分割的Jaccard,Recall和HD95指标分别达到91.226%,93.589%和1.074,与基准U2-Net相比,模型参数量缩减了94.37个百分点;此外,经AC-F算法处理后的区域面积测量百分误差降至1.25%,ICC达到0.998且有95%(76/80)的数据在95%LoA内,能够实现轻量级分割和精确参数测量. 展开更多
关键词 盆底超声图像 轻量化 复合损失函数 深度非对称通道混洗卷积模块 参数测量
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复方苦参注射液联合卡培他滨片同步三维适形调强放疗治疗局部晚期胰腺癌的临床疗效
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作者 韩振坤 杨延辉 +2 位作者 侯鹏 曾炜琦 亢崇照 《中国合理用药探索》 2025年第12期61-67,共7页
目的:探讨复方苦参注射液联合卡培他滨片同步三维适形调强放疗治疗局部晚期胰腺癌(LAPC)患者的临床效果。方法:回顾性收集2021年2月~2023年12月期间某院84例LAPC患者的临床资料,依据治疗方案不同分为对照组(n=40)和观察组(n=44)。所有... 目的:探讨复方苦参注射液联合卡培他滨片同步三维适形调强放疗治疗局部晚期胰腺癌(LAPC)患者的临床效果。方法:回顾性收集2021年2月~2023年12月期间某院84例LAPC患者的临床资料,依据治疗方案不同分为对照组(n=40)和观察组(n=44)。所有患者均先接受注射用盐酸吉西他滨联合注射用紫杉醇(白蛋白结合型)诱导化疗,4个诱导化疗疗程完成后,对照组给予卡培他滨片同步三维适形调强放疗,观察组在对照组治疗基础上加用复方苦参注射液。比较两组患者临床疗效、肿瘤标志物[癌胚抗原(CEA)、糖类抗原19-9(CA19-9)]、免疫功能指标(CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))、不良反应发生情况及随访1年内的生存情况。结果:治疗后,观察组临床缓解率(59.09%)高于对照组(35.00%,P<0.05)。两组患者CEA、CA19-9和CD8^(+)均降低,且观察组低于对照组(P<0.05);CD4^(+)、CD4^(+)/CD8^(+)均升高,且观察组高于对照组(P<0.05)。观察组胃肠道反应、骨髓抑制、失眠、疲劳严重程度≥2级的发生率均低于对照组(P<0.05)。经Log Rank检验,观察组生存率(77.27%)高于对照组(55.00%,χ^(2)=4.555,P=0.033)。结论:复方苦参注射液联合卡培他滨片同步三维适形调强放疗可提高LAPC患者的临床缓解率及生存率,降低肿瘤标志物水平,改善免疫功能。 展开更多
关键词 局部晚期胰腺癌 复方苦参注射液 卡培他滨片 三维适形调强放疗 疗效
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电液系统耦合的水下控制模块失效机理及可靠性研究
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作者 刘致祥 张亮 +4 位作者 王新涛 翟旭 鞠少栋 王继良 杨建义 《化工自动化及仪表》 2025年第4期555-561,共7页
针对水下控制模块的电液系统相互耦合、高故障率的问题,首先分析水下控制模块电控系统和液压系统的失效机理以及各失效模式对系统的影响。研究电液系统可靠性模型关联器件失效状态的结合方法,利用OREDA数据库建立电液系统耦合的水下控... 针对水下控制模块的电液系统相互耦合、高故障率的问题,首先分析水下控制模块电控系统和液压系统的失效机理以及各失效模式对系统的影响。研究电液系统可靠性模型关联器件失效状态的结合方法,利用OREDA数据库建立电液系统耦合的水下控制模块可靠性模型,并提出一种模块化系统分解的可靠性框图建模方法。模型计算得到电控系统、液压系统和电液耦合系统的可靠度曲线和平均无故障时间,水下控制模块电控系统、液压系统和电液耦合系统运行第10年的可靠度分别为85.02%、66.96%和56.93%,平均无故障时间分别为291 980、152 140、118 780 h。在产品设计阶段对水下控制模块进行可靠性分析可大幅提高产品的可靠性,降低产品的维修成本,并且指导工程人员的维修工作。 展开更多
关键词 水下控制模块 电液复合式 失效机理 可靠性框图 可靠性模型 耦合
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基于混合电容储能的500 kW级电磁推进脉冲电源设计
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作者 杨博 巩帅奇 +2 位作者 谭磊 王辰 吴宇桐 《电子元件与材料》 北大核心 2025年第10期1220-1228,共9页
针对500 kW级电磁推进系统对脉冲电源在能量密度、转换效率及输出稳定性方面的高需求,本研究设计了一种基于超级电容与薄膜电容混合储能的电磁推进脉冲电源。该电源利用超级电容组进行能量存储,依靠薄膜电容组完成大功率瞬时放电,通过... 针对500 kW级电磁推进系统对脉冲电源在能量密度、转换效率及输出稳定性方面的高需求,本研究设计了一种基于超级电容与薄膜电容混合储能的电磁推进脉冲电源。该电源利用超级电容组进行能量存储,依靠薄膜电容组完成大功率瞬时放电,通过放电拓扑结构保障电能向负载模块的高效稳定传输,并结合三级保护机制保障系统放电过程的安全性与可靠性。实验结果表明,该电源样机的能量密度为18.3 Wh/kg,转换效率为91.74%,脉冲电流过冲量控制在5.00%以内,各项指标均满足500 kW级电磁推进系统的技术需求。本研究设计的脉冲电源解决了现有中功率电磁推进脉冲电源存在的能量密度低、转换效率差及负载适配性不足等问题。 展开更多
关键词 混合电容储能 电磁推进 脉冲电源 多模块并联放电拓扑 复合控制策略
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大尺寸高厚度功率电源模块塑封工艺
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作者 温丽 王多笑 秦静辰 《电子工艺技术》 2025年第6期45-48,共4页
基于传统的芯片塑料封装技术基础,创新性地提出了高功率密度电源模块一体式塑封成型的工艺方法,实现了板级大功率电源模块封装体积的大幅减小,其质量减轻,散热效率显著提升。为满足大尺寸、高厚度电源模块双面同时塑封、高可靠散热、低... 基于传统的芯片塑料封装技术基础,创新性地提出了高功率密度电源模块一体式塑封成型的工艺方法,实现了板级大功率电源模块封装体积的大幅减小,其质量减轻,散热效率显著提升。为满足大尺寸、高厚度电源模块双面同时塑封、高可靠散热、低应力的塑封需求,优选出了一种具有高流动性、高导热系数和低应力的环氧塑封料。通过优化模块塑封工艺流程和塑封工艺参数,制备出外观和质量较好,电性能正常的塑封电源模块产品,为电源模块产品的整体塑封工艺技术提供重要的参考。 展开更多
关键词 功率电源模块 高厚度 塑封工艺 环氧塑封料
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Traditional Chinese medicine-based phytotherapeutics for junk food-induced obesity and metabolic dysfunction
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作者 Dharmalingam Kirubakaran Durga Nagaraj +2 位作者 Senthamil Selvi Poongavanam Pachaiyappan Murugan Veeran Sethuraman 《Digital Chinese Medicine》 2025年第4期543-557,共15页
Obesity driven by high-sugar and high-fat dietary patterns has become a major global health challenge and is closely associated with metabolic syndrome,diabetes,and cardiovascular disorders.Growing evidence indicates ... Obesity driven by high-sugar and high-fat dietary patterns has become a major global health challenge and is closely associated with metabolic syndrome,diabetes,and cardiovascular disorders.Growing evidence indicates that junk food disrupts lipid metabolism,alters gut microbiota,and triggers chronic inflammation,leading to systemic metabolic dysfunction.Traditional Chinese medicine(TCM),rooted in holistic regulation of organ systems,blood circulation,and energy balance,offers multi-target plant-based strategies for modulating obesity.This review summarizes key mechanisms through which Chinese medicinal plants counteract obesity,including appetite suppression,regulation of lipid metabolism,activation of thermogenesis,modulation of gut microbiota,and anti-oxidative and anti-inflammatory actions.Representative herbs such as Panax ginseng,Nelumbo nucifera,Cinnamomum cassia,Gynostemma pentaphyllum,and Pueraria lobata exhibit lipid-lowering,glucose-regulating,and inflammation-modulating activity in experimental and clinical studies.Overall,TCM herbal therapies provide a holistic and safe approach to correcting metabolic imbalance through multi-pathway regulation.However,standardized formulation,mechanistic validation,and large-scale clinical trials are urgently required to establish their efficacy and translational value.Future work integrating traditional knowledge with biomedical research will help position TCM-based phytotherapy as a scientifically grounded strategy for obesity prevention and management. 展开更多
关键词 Traditional Chinese medicine(TCM) Medicinal plants Bioactive compounds Junk food OBESITY Metabolic dysfunction Gut microbiota regulation Inflammation modulation
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Melatonin Induces Analgesic Effects through MT_(2)Receptor-Mediated Neuroimmune Modulation in the Mice Anterior Cingulate Cortex
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作者 Jian Wang Junxiang Gu +14 位作者 Fujuan Ma Yi Wei Pan Wang Shanming Yang Xianxia Yan Yifan Xiao Keke Xing Anxin Lou Liru Zheng Tingting Cao Dayu Zhu Jinlian Li Luoying Zhang Yunqing Li Tao Chen 《Research》 2025年第2期908-924,共17页
Neuropathic pain(NP)represents a considerable clinical challenge,profoundly impacting patients'quality of life.Presently,pharmacotherapy serves as a primary approach for NP alleviation,yet its efficacy often remai... Neuropathic pain(NP)represents a considerable clinical challenge,profoundly impacting patients'quality of life.Presently,pharmacotherapy serves as a primary approach for NP alleviation,yet its efficacy often remains suboptimal.Melatonin(MLT),a biologically active compound secreted by the pineal gland,has long been associated with promoting and maintaining sleep.Although recent studies suggest analgesic effects of MLT,the underlying mechanism remains largely unknown,particularly its impact on the cortex In this study,we induced an NP model in mice through spared nerve injury(SNI)and observed a considerable,dose-dependent alleviation in NP symptoms following intraperitoneal or anterior cingulate cortex(ACC)administration of MLT.Our findings further indicated that the NP management of MLT is selectively mediated by MLT-related receptor 2(MT_(2)R),rather than MT_(1)R,on neurons and microglia within the ACC.Transcriptome sequencing,complemented by bioinformatics analysis,implicated MLT in the modulation of Ga(i)and immune-inflammatory signals.Specifically,MLT inhibited the excitability level of pyramidal cells in the ACC by activating the Ga(i)signaling pathway.Simultaneously,MLT attenuated M,polarization and promoted M_(2)polarization of microglia,thereby mitigating the inflammatory response and type Il interferon response within the Acc.These findings unveil a hitherto unrecognized molecular mechanism:an MLT-mediated neuroimmune modulation pathway in the ACC mediated by MT_(2)R.This elucidation sheds light on the regulatory character of MLT in chronic nociceptive pain conditions,offering a prospective therapeutic strategy for NP management. 展开更多
关键词 biologically active compound anterior cingulate cortex neuroimmune modulation neuropathic pain pineal glandhas neuropathic pain np represents analgesic effects MELATONIN
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CPM-LFM脉冲压缩雷达移频干扰技术研究
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作者 郭欣 林欢 +1 位作者 于涛 徐亚波 《舰船电子对抗》 2025年第4期24-28,共5页
针对雷达通信一体化系统中连续调相-线性调频(CPM-LFM)复合调制信号在移频干扰下的干扰机理不明确问题,通过理论建模与仿真验证相结合的方法,深入探究移频干扰对该类信号的干扰效应及作用规律。基于时频耦合理论构建了移频干扰的数学模... 针对雷达通信一体化系统中连续调相-线性调频(CPM-LFM)复合调制信号在移频干扰下的干扰机理不明确问题,通过理论建模与仿真验证相结合的方法,深入探究移频干扰对该类信号的干扰效应及作用规律。基于时频耦合理论构建了移频干扰的数学模型,通过推导匹配滤波输出的解析表达式,揭示了干扰信号与目标回波在脉冲压缩处理中的耦合机制。Matlab仿真结果表明,传统移频干扰对LFM信号的“假目标”生成效应在CPM-LFM复合体制中呈现显著差异性。针对传统移频干扰的局限性,本研究创新性地提出随机移频干扰与卷积调制相结合的复合干扰策略。该方法通过引入时变随机移频参数打破雷达信号处理的周期性特征,结合卷积调制重构干扰信号的时频分布特性,仿真结果表明,复合式移频噪声卷积干扰能够对CPM-LFM复合调制信号产生压制效果,进而影响雷达探测能力。 展开更多
关键词 连续调相-线性调频 雷达通信一体化信号 移频干扰 脉冲压缩 复合式干扰
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乳酸杆菌益生作用机制的研究进展 被引量:94
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作者 章文明 汪海峰 刘建新 《动物营养学报》 CAS CSCD 北大核心 2012年第3期389-396,共8页
乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏... 乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。 展开更多
关键词 乳酸杆菌 抗菌物质 竞争黏附 免疫调节 益生作用
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