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Dysfunction of Fronto-Subcortical Circuitry in Fronto-Temporal Dementia
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作者 S. Laurentino E. B. Sougey 《Open Journal of Psychiatry》 2020年第4期171-186,共16页
In the last years, some studies have shown that behavior disorder seems in frontotemporal dementia is related to dysfunction in the fronto-subcortical circuitry. <strong>Objectives:</strong> We did a narra... In the last years, some studies have shown that behavior disorder seems in frontotemporal dementia is related to dysfunction in the fronto-subcortical circuitry. <strong>Objectives:</strong> We did a narrative literature review concerning fronto-subcortical circuitry and frontotemporal dementia (FTD). <strong>Methods:</strong> Manuscripts related to fronto-subcortical network and frontotemporal dementia were selected for further analysis. <strong>Results:</strong> From the executions of simple motor actions to the most complex behaviors like goal-direct behavior and social cognition, the fronto-subcortical circuitry involves an intrigued network of fibers that reaches to basal ganglia nuclei. Recently, researchers have shown five parallel fronto-subcortical circuits integrating and segregating information from the frontal cortex to basal ganglia. Understanding the relationship between the fronto-subcortical circuit dysfunctions and neurodegenerative diseases requires studying the functional anatomy and neurochemical basis involved.<strong> Conclusions:</strong> In this view, it is essential to review the functional anatomy of the fronto-subcortical network, and it’s correlated with clinical aspects to pursuing a better therapeutic approach. 展开更多
关键词 Frontotemporal Dementia fronto-subcortical circuitry Basal Ganglia NEUROTRANSMITTERS fronto-subcortical Syndrome
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Microbleeds in fronto-subcortical circuits are predictive of dementia conversion in patients with vascular cognitive impairment but no dementia 被引量:12
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作者 Yang-Kun Chen Wei-Min Xiao +6 位作者 Wei Li Zhuo-Xin Ni Yong-Lin Liu Li Xu Jian-Feng Qu Chee H.Ng Yu-Tao Xiang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第11期1913-1918,共6页
Cerebral small vessel disease(CSVD) is a common etiology of vascular cognitive impairment with no dementia(V-CIND). Studies have revealed that cerebral microbleeds(CMBs), a feature of CSVD, contribute to cogniti... Cerebral small vessel disease(CSVD) is a common etiology of vascular cognitive impairment with no dementia(V-CIND). Studies have revealed that cerebral microbleeds(CMBs), a feature of CSVD, contribute to cognitive impairment. However, the association between CMBs and dementia conversion in individuals with V-CIND is still unclear. Here, we analyzed the predictive role of CMBs in the conversion from V-CIND to dementia in CSVD patients. We recruited and prospectively assessed 85 patients with CSVD and V-CIND. V-CIND was evaluated using a series of comprehensive neuropsychological scales, including the Chinese version of the Montreal Cognitive Assessment and the Clinical Dementia Rating. MRI assessments were used to quantify lacunar infarcts, white matter hyperintensities, CMBs, and medial temporal lobe atrophy. Eighty-two of the 85 patients completed the assessment for dementia conversion at a 1-year follow-up assessment. Multivariate logistic regression analyses were conducted to examine independent clinical and MRI variables associated with dementia conversion. Twenty-four patients(29.3%) had converted to dementia at the 1-year follow-up, and these individuals had significantly more CMBs in the fronto-subcortical circuits. Multivariate logistic regression analyses revealed that the patients with CMBs in the fronto-subcortical circuits(odds ratio = 4.4; 95% confidence interval: 1.602-12.081, P = 0.004) and 5 or more CMBs overall(odds ratio = 17.6, 95% confidence interval: 3.23-95.84, P = 0.001) had a significantly increased risk of dementia at the 1-year follow-up. These findings indicate that CMBs in the fronto-subcortical circuits may be predictive of dementia conversion in CSVD patients with V-CIND, and thus extend the clinical significance of CMBs. 展开更多
关键词 cerebrovascular disease stroke cerebral microbleeds cognitive impairment fronto-subcortical circuits small vessel disease whitematter hyperintensities lacunar infarct magnetic resonance imaging subcortical ischemic vascular disease
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Mapping Fear-Related Neural Activity and Circuitry Changes Following Prophylactic Administration of(R,S)-Ketamine and(2S,6S)-Hydroxynorketamine
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作者 Minzhu Li Li Cheng 《Neuroscience Bulletin》 2025年第5期925-928,共4页
Fear memory,a predictive and protective mechanism in potentially hostile environments,elicits defensive behavioral responses that have evolved to help organisms avoid harm and ensure survival.However,excessive fear me... Fear memory,a predictive and protective mechanism in potentially hostile environments,elicits defensive behavioral responses that have evolved to help organisms avoid harm and ensure survival.However,excessive fear memories may contribute to the onset of various psychological disorders,such as panic disorder,phobias,and post-traumatic stress disorder(PTSD). 展开更多
关键词 fear memories prophylactic administration psychological disorderssuch fear memorya fear related circuitry changes panic disorderphobiasand neural activity
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A SWITCHED HYPERCHAOTIC SYSTEM AND ITS FPGA CIRCUITRY IMPLEMENTATION 被引量:1
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作者 Qi Aixue Zhang Chengliang Wang Honggang 《Journal of Electronics(China)》 2011年第3期383-388,共6页
This paper introduces a switched hyperchaotic system that changes its behavior randomly from one subsystem to another via two switch functions, and its characteristics of symmetry, dissipation, equilibrium, bifurcatio... This paper introduces a switched hyperchaotic system that changes its behavior randomly from one subsystem to another via two switch functions, and its characteristics of symmetry, dissipation, equilibrium, bifurcation diagram, basic dynamics have been analyzed. The hardware implementation of the system is based on Field Programmable Gate Array (FPGA). It is shown that the experimental results are identical with numerical simulations, and the chaotic trajectories are much more complex. 展开更多
关键词 Chaotic sequence HYPERCHAOS Field Programmable Gate Array (FPGA) circuitry implementation
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Reorganization of spinal neural circuitry and functional recovery after spinal cord injury 被引量:1
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作者 Raffaele Nardone Eugen Trinka 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第2期201-202,共2页
The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury (SCI). Adaptive changes within spared neur... The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury (SCI). Adaptive changes within spared neuronal circuits may occur at cortical, brainstem, or spinal cord level, both above and below a spinal lesion (Bareyre et al., 2004). At each level the reorganization is a very dynamic process, and its degree is highly variable, depending on several factors, including the age of the subject when SCI has occurred and the rehabilitative therapy. The use of electrophysiological techniques to assess these functional changes in neural networks is of great interest, because invasive methodologies as employed in preclinical models can obviously not be used in clinical studies. 展开更多
关键词 SCI Reorganization of spinal neural circuitry and functional recovery after spinal cord injury TSR
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A Short Glance at the Neural Circuitry Mechanism Underlying Depression
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作者 Chanyi Lu Qiqin Li +2 位作者 Yaoyao Li Yun Wang Yun-Feng Zhang 《World Journal of Neuroscience》 2016年第3期184-192,共9页
Depression leads to a large social burden because of its substantial impairment and disability in everyday activities. The prevalence and considerable impact of this disorder call for a better understanding of its pat... Depression leads to a large social burden because of its substantial impairment and disability in everyday activities. The prevalence and considerable impact of this disorder call for a better understanding of its pathophysiology to improve the diagnosis, treatment and prevention. Though productive animal models and pathophysiological theories have been documented, it is still very far to uncover the complex array of symptoms caused by depression. Moreover, the neural circuitry mechanism underlying behavioral changes in some depression-like behavior animals is still limited. Changes in the neural circuitry of amygdala, dorsal raphe nucleus, ventral tegmental area, hippocampus, locus coeruleus and nucleus accumbens are related to depression. However, the interactions between individual neural circuitry of different brain areas, have not yet been fully elucidated. The purpose of the present review is to examine and summarize the current evidence for the pathophysiological mechanism of depression, with a focus on the neural circuitry, and emphasize the necessity and importance of integrating individual neural circuitry in different brain regions to understand depression. 展开更多
关键词 PATHOPHYSIOLOGY Depression-Like Behavior Neural circuitry
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Aberrant dynamic functional connectivity of thalamocortical circuitry in major depressive disorder
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作者 Weihao ZHENG Qin ZHANG +7 位作者 Ziyang ZHAO Pengfei ZHANG Leilei ZHAO Xiaomin WANG Songyu YANG Jing ZHANG Zhijun YAO Bin HU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2024年第10期857-877,共21页
Thalamocortical circuitry has a substantial impact on emotion and cognition.Previous studies have demonstrated alterations in thalamocortical functional connectivity(FC),characterized by region-dependent hypo-or hyper... Thalamocortical circuitry has a substantial impact on emotion and cognition.Previous studies have demonstrated alterations in thalamocortical functional connectivity(FC),characterized by region-dependent hypo-or hyper-connectivity,among individuals with major depressive disorder(MDD).However,the dynamical reconfiguration of the thalamocortical system over time and potential abnormalities in dynamic thalamocortical connectivity associated with MDD remain unclear.Hence,we analyzed dynamic FC(dFC)between ten thalamic subregions and seven cortical subnetworks from resting-state functional magnetic resonance images of 48 patients with MDD and 57 healthy controls(HCs)to investigate time-varying changes in thalamocortical FC in patients with MDD.Moreover,dynamic laterality analysis was conducted to examine the changes in functional lateralization of the thalamocortical system over time.Correlations between the dynamic measures of thalamocortical FC and clinical assessment were also calculated.We identified four dynamic states of thalamocortical circuitry wherein patients with MDD exhibited decreased fractional time and reduced transitions within a negative connectivity state that showed strong correlations with primary cortical networks,compared with the HCs.In addition,MDD patients also exhibited increased fluctuations in functional laterality in the thalamocortical system across the scan duration.The thalamo-subnetwork analysis unveiled abnormal dFC variability involving higher-order cortical networks in the MDD cohort.Significant correlations were found between increased dFC variability with dorsal attention and default mode networks and the severity of symptoms.Our study comprehensively investigated the pattern of alteration of the thalamocortical dFC in MDD patients.The heterogeneous alterations of dFC between the thalamus and both primary and higher-order cortical networks may help characterize the deficits of sensory and cognitive processing in MDD. 展开更多
关键词 Major depressive disorder Resting-state functional magnetic resonance imaging Thalamocortical circuitry Dynamic functional connectivity Dynamic laterality
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Brain reward circuitry:The overlapping neurobiology of trauma and substance use disorders
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作者 Timothy I Michaels Emily Stone +3 位作者 Sonali Singal Vladan Novakovic Robert L Barkin Stacy Barkin 《World Journal of Psychiatry》 SCIE 2021年第6期222-231,共10页
Mental health symptoms secondary to trauma exposure and substance use disorders(SUDs)co-occur frequently in both clinical and community samples.The possibility of a shared aetiology remains an important question in tr... Mental health symptoms secondary to trauma exposure and substance use disorders(SUDs)co-occur frequently in both clinical and community samples.The possibility of a shared aetiology remains an important question in translational neuroscience.Advancements in genetics,basic science,and neuroimaging have led to an improved understanding of the neural basis of these disorders,their frequent comorbidity and high rates of relapse remain a clinical challenge.This project aimed to conduct a review of the field’s current understanding regarding the neural circuitry underlying posttraumatic stress disorder and SUD.A comprehensive review was conducted of available published literature regarding the shared neurobiology of these disorders,and is summarized in detail,including evidence from both animal and clinical studies.Upon summarizing the relevant literature,this review puts forth a hypothesis related to their shared neurobiology within the context of fear processing and reward cues.It provides an overview of brain reward circuitry and its relation to the neurobiology,symptomology,and phenomenology of trauma and substance use.This review provides clinical insights and implications of the proposed theory,including the potential development of novel pharmacological and therapeutic treatments to address this shared neurobiology.Limitations and extensions of this theory are discussed to provide future directions and insights for this shared phenomena. 展开更多
关键词 Posttraumatic stress disorder Substance abuse Reward circuitry Mesolimbic Neurobiology
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非对称Buck-Boost电路及锂电池组主动均衡策略研究
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作者 李善寿 钱龙 +2 位作者 叶伟 黄梅初 谢陈磊 《电源技术》 北大核心 2025年第4期814-823,共10页
针对当前均衡电路拓扑和控制策略存在均衡速度慢、均衡路径单一等问题,提出一种基于非对称Buck-Boost电路电池组均衡控制电路拓扑,分析了非对称Buck-Boost电路实现单体-单体和多体-非对称多体均衡控制原理。以锂电池荷电状态(SOC)为均... 针对当前均衡电路拓扑和控制策略存在均衡速度慢、均衡路径单一等问题,提出一种基于非对称Buck-Boost电路电池组均衡控制电路拓扑,分析了非对称Buck-Boost电路实现单体-单体和多体-非对称多体均衡控制原理。以锂电池荷电状态(SOC)为均衡变量,构建电池组状态空间模型,利用二次规划算法滚动优化均衡电流。通过调节开关管占空比控制实现锂电池组SOC均衡。在MATLAB/Simulink仿真平台下搭建了非对称Buck-Boost电路及主动均衡控制策略模型。针对马里兰大学公开锂电池充放电实验数据集进行仿真验证,结果表明,非对称Buck-Boost电路均衡拓扑和主动均衡控制策略模型可以快速实现锂电池组SOC均衡,与传统的拓扑和控制策略相比,均衡时间缩短30.9%以上。 展开更多
关键词 锂电池组 非对称Buck-Boost电路 SOC均衡 模型预测控制
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三种降糖药对T2DM患者嗅觉神经环路重塑价值的fMRI研究
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作者 吴敏 李欣 +8 位作者 张雯 李卫萍 张易 李倩 申欣怡 张鑫 计成 毕艳 张冰 《磁共振成像》 北大核心 2025年第6期10-20,26,共12页
目的探讨三种临床常见的降糖药(利拉鲁肽、达格列净和阿卡波糖)对2型糖尿病(type 2 diabetes mellitus,T2DM)患者嗅觉易损脑区与全脑之间功能连接(functional connectivity,FC)的影响。材料与方法本研究包括基线期和药物治疗两个阶段的... 目的探讨三种临床常见的降糖药(利拉鲁肽、达格列净和阿卡波糖)对2型糖尿病(type 2 diabetes mellitus,T2DM)患者嗅觉易损脑区与全脑之间功能连接(functional connectivity,FC)的影响。材料与方法本研究包括基线期和药物治疗两个阶段的研究。基线期研究招募糖代谢正常对照(normal control,NC)组51例和T2DM组191例。评估两组间FC、认知功能、嗅觉行为学及临床指标的差异。药物治疗随访研究中,36例经过二甲双胍治疗仍血糖控制不佳的T2DM患者被随机平均分配到三个治疗组:利拉鲁肽组(n=12)、达格列净组(n=12)和阿卡波糖组(n=12),为期16周,采用随机对照试验(randomized controlled trial,RCT)评估三种药物对FC、认知功能和嗅觉行为学的影响。结果利拉鲁肽治疗16周后,T2DM患者血糖明显改善,减重效果显著;延迟记忆改善(t=−6.148,P<0.001)和嗅觉阈值升高(t=−2.321,P=0.040);左侧丘脑和左侧枕下回及右侧丘脑和左侧梭状回间FC的代偿升高得到恢复(GRF校正,体素水平P<0.005,团块水平P<0.05),而阿卡波糖和达格列净治疗前后差异无统计学意义(P>0.05)。结论本研究表明,利拉鲁肽能够显著改善两侧丘脑和左侧枕叶间的FC、认知功能以及嗅觉阈值,利拉鲁肽具有除代谢益处之外的神经保护作用,而达格列净和阿卡波糖没有表现出嗅觉、认知及脑功能保护作用。 展开更多
关键词 2型糖尿病 降糖药物 胰高血糖素样肽-1受体激动剂 功能连接 嗅觉神经环路 磁共振成像
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模拟电子电路一流课程教学改革与实践
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作者 刘洋 郑传涛 《中国现代教育装备》 2025年第13期78-80,87,共4页
基于OBE教育理念,按照“模式—资源—评价”协同改革的思路,建设模拟电子电路一流课程。构建“四三式”教学模式,建立“3主体、4形式”评价体系,将“学、践、研、创”有机结合,提升了学生电子工程实践能力、跨界融合和创新驱动能力,为... 基于OBE教育理念,按照“模式—资源—评价”协同改革的思路,建设模拟电子电路一流课程。构建“四三式”教学模式,建立“3主体、4形式”评价体系,将“学、践、研、创”有机结合,提升了学生电子工程实践能力、跨界融合和创新驱动能力,为同类型课程教学改革提供一定的借鉴。 展开更多
关键词 四三式 教学模式 一流课程 模拟电子电路
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基于伏隔核神经环路探讨抑郁症的发病机制及针灸治疗的研究进展 被引量:1
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作者 孙洪艺 骆思宏 +3 位作者 张成宇 孟子杭 陈卓 李晓宁 《实用医学杂志》 北大核心 2025年第22期3618-3624,共7页
抑郁症发生发展与大脑奖赏和情绪调节环路功能失调密切相关,伏隔核(nucleus accumben,NAc)作为奖赏系统的核心枢纽,与腹侧被盖区(ventral tegmental area,VTA)、内侧前额叶皮质(medial prefrontal cortex,mPFC)、杏仁核(amygdala,AMY)... 抑郁症发生发展与大脑奖赏和情绪调节环路功能失调密切相关,伏隔核(nucleus accumben,NAc)作为奖赏系统的核心枢纽,与腹侧被盖区(ventral tegmental area,VTA)、内侧前额叶皮质(medial prefrontal cortex,mPFC)、杏仁核(amygdala,AMY)、海马(hippocampus,HIP)及丘脑室旁核(paraventricular nucleus of the thalamus,PVT)等脑区构成的神经环路异常已被证实与抑郁症状存在显著关联。针刺通过多靶点起效的作用特点,符合抑郁症这一多病因、多系统失调的情感障碍特征。现基于NAc为中心的脑神经环路,系统梳理其在抑郁症发生发展中的功能变化及针刺干预的潜在机制,揭示针刺通过调节VTA-NAc多巴胺能传导、增强mPFC-NAc环路的神经递质平衡、双向调节AMY-NAc环路的情绪稳定、减轻HIP-NAc谷氨酸过度活跃状态及优化丘脑-NAc环路的兴奋性传递,实现对抑郁症的整体性改善。此外,该综述聚焦于环路层面的系统整合,突出了针刺抗抑郁的实用性及其机制研究进展,以期为临床治疗提供更可靠的理论支撑与实践指导。 展开更多
关键词 伏隔核 针刺 抑郁症 神经环路 研究进展
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Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury 被引量:2
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作者 Xinyu You Lin Niu +4 位作者 Jiafeng Fu Shining Ge Jiangwei Shi Yanjun Zhang Pengwei Zhuang 《Neural Regeneration Research》 SCIE CAS 2025年第8期2153-2168,共16页
Traumatic brain injury is a prevalent disorder of the central nervous system.In addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for pati... Traumatic brain injury is a prevalent disorder of the central nervous system.In addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are lacking.Intestinal dysfunction is a significant consequence of traumatic brain injury.Being the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous system.The gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated complications.We comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut microbiota.Additionally,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain injury.This review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effects of the“brain-gut-microbiota axis.” 展开更多
关键词 traumatic brain injury brain-gut-microbiome axis gut microbiota NEUROIMMUNE immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry
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肾上腺素能与神经母细胞瘤的关系及其靶向治疗的研究进展
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作者 杨洋 杨霞 《中山大学学报(医学科学版)》 北大核心 2025年第6期907-919,共13页
神经母细胞瘤(NB)是儿童最常见的颅外实体恶性肿瘤,是肾上腺素能来源的神经内分泌肿瘤,其临床表现具有高度异质性。高危NB患儿预后不佳,即使经过高强度治疗,仍会出现复发或转移。NB细胞主要包括肾上腺素能(ADRN)和间充质(MES)两个亚型,... 神经母细胞瘤(NB)是儿童最常见的颅外实体恶性肿瘤,是肾上腺素能来源的神经内分泌肿瘤,其临床表现具有高度异质性。高危NB患儿预后不佳,即使经过高强度治疗,仍会出现复发或转移。NB细胞主要包括肾上腺素能(ADRN)和间充质(MES)两个亚型,前者与分化相关,对诱导分化和化疗药物更敏感;后者与侵袭性、化疗抵抗相关。研究表明ADRN和MES两种亚型间的谱系转化会导致肿瘤异质性,可能引发化疗耐药或复发。通过解析二者相互转化过程中的分子机制,对于克服谱系转化引发的耐药性和靶向ADRN治疗高危NB具有重要意义。本文系统综述了肾上腺素能在神经母细胞瘤发生发展中的作用及其自身分子调控机制,并归纳总结了靶向ADRN在NB临床诊治中的相关研究进展,旨在为未来NB临床治疗和预防提供参考依据。 展开更多
关键词 神经母细胞瘤 肾上腺素能 高危 核心调控环路 靶向治疗
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面向双马树脂基复合材料电场驱动微3D打印高精度电路
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作者 刘亚东 张厚超 +6 位作者 朱晓阳 许权 李义睿 韩志峰 赵佳伟 刘琦 兰红波 《复合材料学报》 北大核心 2025年第1期235-249,共15页
纤维改性双马树脂基复合材料凭借其优异的力学性能、耐高温、耐腐蚀特性,被广泛应用于航空航天、智能蒙皮、共形天线、电磁屏蔽、高频电路基板、电加热等领域。然而,由于石英纤维增强双马树脂基复合材料具有非平整、异质、各向异性的特... 纤维改性双马树脂基复合材料凭借其优异的力学性能、耐高温、耐腐蚀特性,被广泛应用于航空航天、智能蒙皮、共形天线、电磁屏蔽、高频电路基板、电加热等领域。然而,由于石英纤维增强双马树脂基复合材料具有非平整、异质、各向异性的特点,在此基材上简单、高效、低成本制造高分辨率微细电路是当前亟待解决的难题。本文提出了一种基于电场驱动微3D打印在石英纤维增强双马树脂基复合材料上制造高精度电路的新方法,阐述了基本成形原理和关键技术实现,探究了非平整异质复合材料表面电场分布特点和场强变化规律,提出通过调节电场强度阈值实现稳定打印的策略;通过实验揭示了主要工艺参数对制造电路精度、形貌以及性能的影响规律,并结合优化的工艺窗口,实现了最小线宽50μm的多种图案微细电路的制造。制造的典型样件电导率为4.0×10^(7)S/m,经100次附着力实验和100 min超声实验后电阻变化率在1%左右;在电加热应用方面展现出优异的热响应速度,在3 V电压下最高温度可达158℃,能够在200 s内实现除冰。该技术为高效低成本制造纤维改性双马树脂复合材料基微细电路提供了一种有效方法,显示出良好的工业化应用前景。 展开更多
关键词 电场驱动微3D打印 石英纤维增强双马树脂基复合材料 非平整异质基材 增材制造 高精度电路
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高g值冲击下板级电路的动态响应研究
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作者 郑高泽 徐鹏 《测试技术学报》 2025年第3期337-345,共9页
新型动能武器中的弹载电子封装设备模块在连续多脉高过载冲击作用下会产生不可逆的损伤,从而导致其失效,影响弹药的杀伤效能。在此背景下选取电子封装设备中的板级电路为研究对象,从理论上对基板和带有集中质量的电路板进行振动分析,得... 新型动能武器中的弹载电子封装设备模块在连续多脉高过载冲击作用下会产生不可逆的损伤,从而导致其失效,影响弹药的杀伤效能。在此背景下选取电子封装设备中的板级电路为研究对象,从理论上对基板和带有集中质量的电路板进行振动分析,得出了其固有频率表达式。并利用有限元软件ANSYS对板级电路进行了模态分析,其主要振型是在电路板Z轴方向的弯曲振动。利用显式动力分析软件LS-DYNA对板级电路进行了连续多脉冲高过载冲击下的仿真分析,4种不同类型的连续多脉冲加速度载荷下印刷电路板(Printed Circuit Board,PCB)上的最大等效应力始终出现在螺柱孔位附近。且随着加载载荷的脉冲间隔时间减小,PCB板的最大等效应力增大。利用冲击试验台对板级电路进行高过载冲击试验,方板和圆板在70804g和91762g载荷下均未发生元器件脱落、引线断裂等现象,故板级电路具有较好的抗高g值冲击性能,不容易发生失效。 展开更多
关键词 板级电路 集中质量 模态分析 连续多脉冲 高g值冲击
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A New Pathway Mediating Pain Sensitization after Active Sleep Deprivation
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作者 Xinyue Zhao Yanrong Zheng Zhong Chen 《Neuroscience Bulletin》 2025年第3期543-545,共3页
Sleep is an indispensable part of life−its deficiency has significant implications for overall health and wellbeing[1].In today’s fast-paced society,sleep loss from either stressful or non-stressful origins has becom... Sleep is an indispensable part of life−its deficiency has significant implications for overall health and wellbeing[1].In today’s fast-paced society,sleep loss from either stressful or non-stressful origins has become prevalent.Specifically,active sleep deprivation(ASD),resulting from extended use of smartphones and other recreational activities,has risen as a global health issue.Clinical research has underscored a strong correlation between chronic pain and inadequate sleep[2].The relationship between pain and sleep is reciprocal:pain disturbs sleep,while poor sleep quality,in turn,reduces pain tolerance and exacerbates spontaneous pain sensations[3].While these interplays are well-documented in cases of passive sleep deprivation(PSD)associated with external pressures or illnesses,understanding how and which regions of the brain collaborate to recalibrate the intricate neural circuitry governing pain perception during ASD remains a crucial yet unresolved frontier. 展开更多
关键词 chronic pain sleep deprivation active sleep deprivation pain sensitization sleep deprivation asd resulting pain perception neural circuitry
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Bioinspired cascade nanozymes reprogram osteoarthritic joints:Mn-Nb_(2)C-CeO_(2)mediated immuno-redox circuitry for self-healing cartilage
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作者 Yan Ma Yufei Liu +6 位作者 Pan Chen Yingfeng Su Zizheng Chen Xiangqian Fang Yujun Zhang Junxin Chen Wenbin Xu 《Nano Research》 2026年第1期985-1002,共18页
Osteoarthritis(OA),a debilitating joint disorder affecting millions worldwide,is characterized by persistent inflammation,oxidative stress,and irreversible cartilage breakdown,yet remains without diseasemodifying ther... Osteoarthritis(OA),a debilitating joint disorder affecting millions worldwide,is characterized by persistent inflammation,oxidative stress,and irreversible cartilage breakdown,yet remains without diseasemodifying therapies.Inspired by natural enzymatic cascades,we developed a bioinspired nanocomposite hydrogel,N,S-doped Mn-Nb(C-CeO),that mimics endogenous antioxidant pathways to reprogram the OA microenvironment.This system combines N,Sdoped Mn-Nb_(2)C MXene nanosheets with CeO_(2)nanozymes within a boronate ester-crosslinked hydrogel,forming an“immuno-redox circuitry”with four synergistic functions:(1)cascade reactive oxygen species(ROS)scavenging via superoxide dismutase-like Mn-Nb_(2)C and catalase-like CeO_(2),amplified by photothermal enhancement under near-infrared irradiation;(2)broad reactive nitrogen species clearance,removing peroxynitrite(ONOO^(-)),nitric oxide(NO),and nitroxyl(NO^(-))to mitigate inflammation;(3)immunomodulation through Mn^(2+)-activated cGAS-STING signaling,which promoted macrophage polarization toward the M2 phenotype,concomitantly reducing the levels of pro-inflammatory cytokines such as interleukin-1 beta(IL-1β)and tumor necrosis factor-alpha(TNF-α);(4)cartilage regeneration via pH/ROS-responsive simvastatin(SIM)release and nanocatalysis,upregulating SRY-box transcription factor 9(SOX9)and Col2a1 while inhibiting matrix metalloproteinase-13(MMP-13)and a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5).In a murine OA model,the system reduced synovitis by 60%,restored 80% of cartilage thickness,and suppressed osteophyte formation,outperforming singlecomponent treatments.This strategy pioneers a“self-healing cartilage”approach by integrating nanocatalysis with immunoengineering for transformative OA therapy. 展开更多
关键词 bioinspired nanozymes nitrogen doping osteoarthritis immuno-redox circuitry cartilage reprogramming MXene hydrogels
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基于EXB841的IGBT驱动电路设计及优化 被引量:28
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作者 丁祖军 郑建勇 +3 位作者 梅军 苏麟 柴继涛 吴恒荣 《电力自动化设备》 EI CSCD 北大核心 2004年第6期37-40,共4页
介绍了绝缘栅双极型晶体管IGBT(InsulatedGateBipolarTransistor)器件驱动电路设计的一般要求,对EXB841芯片的工作过程作了深入的分析,研究了EXB841对IGBT的开通和关断以及过流保护的原理,指出了用EXB841直接驱动IGBT时存在的问题和不足... 介绍了绝缘栅双极型晶体管IGBT(InsulatedGateBipolarTransistor)器件驱动电路设计的一般要求,对EXB841芯片的工作过程作了深入的分析,研究了EXB841对IGBT的开通和关断以及过流保护的原理,指出了用EXB841直接驱动IGBT时存在的问题和不足,主要是过流保护的阀值太高、关断不可靠及在软关断时没有对外部输入信号进行封锁。同时,提出了针对这些不足在设计驱动电路时应当采取的几种有效方法。最后,运用EXB841及其他器件设计和优化了一个IGBT的驱动电路,该驱动电路通过电力电子仿真软件PSPICE(SimulationProgramwithICEmphasis)仿真和试验证明能够有效地对IGBT器件进行驱动和过电流保护。 展开更多
关键词 绝缘栅双极型晶体管 EXB841 驱动电路
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支路数对热泵空调中冷凝和蒸发两用换热器性能的影响 被引量:28
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作者 黄东 陈群 袁秀玲 《西安交通大学学报》 EI CAS CSCD 北大核心 2007年第5期543-548,共6页
在空气的进口状态和流量、换热器的几何结构尺寸、管路排布方式等相同时,研究了支路数对蒸发和冷凝两用换热器流动与传热性能的影响规律.结果表明:随支路数增多,空气与制冷剂间的传热温差会增大,但总传热系数却会变小;室内换热器作蒸... 在空气的进口状态和流量、换热器的几何结构尺寸、管路排布方式等相同时,研究了支路数对蒸发和冷凝两用换热器流动与传热性能的影响规律.结果表明:随支路数增多,空气与制冷剂间的传热温差会增大,但总传热系数却会变小;室内换热器作蒸发器时,换热量先升后降,最小值比最大值小23.2%,存在使换热量最大的最佳支路数,在支路数小于或大于最佳支路数时,换热量的主导因素分别为传热温差与总传热系数;室内换热器作冷凝器时,换热量随支路数增多单调递减,最小值比最大值小40.55%,总传热系数始终是制约换热量的主导因素.因此,为协调并同时提高制冷、制热循环的效率,需要优化热泵系统中换热器的支路数. 展开更多
关键词 支路数 冷凝器 蒸发器 热泵 热泵空调
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