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Does transcranial direct current stimulation enhance the hypoalgesic effect of exercise?
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作者 Aidan Lewis Ben Rattray +1 位作者 Constantino Toufexis Andrew Flood 《Sports Medicine and Health Science》 2026年第1期102-109,共8页
Exercise produces a decrease in pain sensitivity via an effect called exercise-induced hypoalgesia(EIH).Transcranial direct current stimulation(tDCS),acting on similar analgesic mechanisms as EIH,represents a potentia... Exercise produces a decrease in pain sensitivity via an effect called exercise-induced hypoalgesia(EIH).Transcranial direct current stimulation(tDCS),acting on similar analgesic mechanisms as EIH,represents a potential complementary intervention that may amplify the effects of exercise on pain.This study aimed to explore if anodal tDCS could enhance the effect of exercise on pain compared to exercise alone.A total of 35 healthy participants aged 19–37 years completed a familiarisation session followed by two separate sessions where active and sham tDCS was applied in a randomised cross-over design.The familiarisation session involved familiarisation to the pain assessment and exercise tasks,while the subsequent tDCS sessions involved pain sensitivity assessment,exercise and either anodal tDCS or sham tDCS.tDCS doses were applied at 2 mA over the primary motor cortex for 10 min,with the reference electrode placed over the contralateral supraorbital area.The exercise task involved a sustained isometric grip strength contraction at 35%of maximal voluntary contraction(MVC)until volitional exhaustion.Pain sensitivity was evaluated as pressure pain threshold before tDCS,after tDCS,and after exercise.Across both tDCS conditions,pain threshold was higher after exercise when compared to pre-and post-tDCS measurement.This increase in pain threshold did not differ between active and sham tDCS conditions.Our findings suggest that the hypoalgesic effects of active anodal tDCS over the motor cortex prior to exercise are no greater than the effects of sham tDCS prior to exercise. 展开更多
关键词 Transcranial direct current stimulation Grip strength Pain sensitivity Time to exhaustion Pain pressure threshold TDCS
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电弧增材制造高强度Al-Mg-Sc系合金研究进展冶金缺陷、微观组织和力学性能
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作者 马成勇 侯旭儒 +4 位作者 赵琳 阚成玲 曹洋 彭云 田志凌 《金属学报》 北大核心 2026年第1期29-46,共18页
电弧增材制造(WAAM)技术因其制造成本低、沉积效率高、成形构件无尺寸限制等特点,成为大型复杂构件一体化制造最具潜力的技术之一,尤其适用于焊接性能优异的Al-Mg-Sc系合金。基于此,本文详细综述了WAAM成形Al-Mg-Sc系合金的研究进展,包... 电弧增材制造(WAAM)技术因其制造成本低、沉积效率高、成形构件无尺寸限制等特点,成为大型复杂构件一体化制造最具潜力的技术之一,尤其适用于焊接性能优异的Al-Mg-Sc系合金。基于此,本文详细综述了WAAM成形Al-Mg-Sc系合金的研究进展,包括冶金缺陷、微观组织和成形性能。在WAAM中,通过优化丝材成分、打印工艺和引入层间搅拌摩擦加工(FSP)均能有效降低气孔率,改善微观组织和提升合金性能。成形合金最低气孔率约为0.026%;由于Sc强烈的微合金化作用,微观组织均为等轴晶,平均晶粒尺寸约为10μm,成形合金表现出优异的性能,直接时效后,合金最高抗拉强度可达470 MPa,且具有优异的塑性。然而,WAAM专用Al-Mg-Sc系合金丝材的研发、冶金缺陷形成的内在机理、粗大微米级Al3(Sc1-x,Zrx)相的调控以及多性能的探究仍需进一步解决。最后,基于机器学习在智能制造中的优势,对未来机器学习在WAAM成形中的应用进行了展望:正向性能预测与逆向成分/工艺求解,从而加速WAAM专用高强度铝合金丝材研发,并降低生产成本、缩短研制周期。 展开更多
关键词 电弧增材制造 高强度Al-Mg-sc合金 冶金缺陷 组织和性能 机器学习
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Zr对Al-Cu-Mg-Ag-Sc耐热合金组织和性能的影响
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作者 周飞月 郑云鹏 +3 位作者 鲁强 王金三 李凯 杜勇 《特种铸造及有色合金》 北大核心 2026年第2期218-224,共7页
Al-Cu-Mg-Ag合金的Sc微合金化具有双刃剑效应,一方面Sc元素会消耗Cu元素形成AlCuSc第二相,降低合金强度,另一方面,其可以促进Ω相原位转变为具有优异耐热性能的V-AlCuSc相,显著提高其服役温度。协同提升合金室温强度以及耐热性能成为含S... Al-Cu-Mg-Ag合金的Sc微合金化具有双刃剑效应,一方面Sc元素会消耗Cu元素形成AlCuSc第二相,降低合金强度,另一方面,其可以促进Ω相原位转变为具有优异耐热性能的V-AlCuSc相,显著提高其服役温度。协同提升合金室温强度以及耐热性能成为含Sc耐热铝合金的关键问题。通过在Al-Cu-Mg-Ag-Sc耐热合金中添加不同含量的Zr,尝试与过量Sc结合形成Al_(3)(Sc,Zr)颗粒,促进具有优异热稳定性能的Al_(3)(Sc,Zr)与V-AlCuSc相协同析出,从而提高合金的高温服役性能。拉伸性能测试以及多尺度透射电镜表征结果表明,Zr的加入可以有效地细化晶粒,与Sc结合形成Al_(3)(Sc,Zr)颗粒促进合金析出相析出,并形成Al_(3)(Sc,Zr)颗粒与V-AlCuSc相共存的结构,使合金在峰时效和400℃热暴露后均具有更高的强度和塑性。 展开更多
关键词 AL-CU-MG-AG合金 析出相 Al_(3)(sc Zr)颗粒 V-AlCusc 热稳定性
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Ionospheric F-region currents estimated from Macao Science Satellite-1 and Swarm satellite magnetic data 被引量:1
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作者 JuYuan Xu HongBo Yao Keke Zhang 《Earth and Planetary Physics》 2025年第3期731-739,共9页
Accurate modeling of Earth's ionospheric F-region currents is essential for refining geomagnetic field models and understanding magnetosphere-ionosphere coupling.In this study,we develop averaged models to charact... Accurate modeling of Earth's ionospheric F-region currents is essential for refining geomagnetic field models and understanding magnetosphere-ionosphere coupling.In this study,we develop averaged models to characterize F-region currents using magnetic data from the MSS-1(Macao Science Satellite-1) and Swarm satellite missions.Our approach employs a toroidal field representation,utilizing spherical harmonics to capture spatial variations and Fourier series to represent temporal dynamics.Two models,Model-A and Model-B,derived from distinct datasets,are constructed to represent current patterns at altitudes of 450 km and 512 km,respectively.Our models successfully capture the primary spatial structures and seasonal variations of polar field-aligned currents.Additionally,they accurately reproduce the localized inter-hemispheric field-aligned currents observed in mid and low latitudes during solstices,particularly between 14:00 and 16:00 magnetic local times.These findings enhance our understanding of ionospheric F-region currents and contribute to more precise geomagnetic field modeling. 展开更多
关键词 Macao science Satellite-1 SWARM field-aligned currents GEOMAGNETISM ionosphere
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复合添加微量Sc、Zr对Al-6.0Mg-0.4Mn合金高温变形行为的影响
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作者 杨佳楠 姜锋 +5 位作者 白皓元 肖泽宇 龙梦君 吴飞飞 童蒙蒙 路丽英 《轻合金加工技术》 2026年第1期37-45,51,共10页
采用电子背散射衍射仪(EBSD)、透射电子显微镜(TEM)和高温力学性能测试设备研究了Al-6.0Mg-0.4Mn合金和Al-6.0Mg-0.4Mn-0.25Sc-0.1Zr合金在高温拉伸过程中的组织性能演变。结果表明,复合添加的Sc、Zr在Al-6.0Mg-0.4Mn合金基体中形成了... 采用电子背散射衍射仪(EBSD)、透射电子显微镜(TEM)和高温力学性能测试设备研究了Al-6.0Mg-0.4Mn合金和Al-6.0Mg-0.4Mn-0.25Sc-0.1Zr合金在高温拉伸过程中的组织性能演变。结果表明,复合添加的Sc、Zr在Al-6.0Mg-0.4Mn合金基体中形成了大量弥散分布的Al_(3)(Sc,Zr)粒子。这些粒子能够钉扎位错和晶界,使合金在高温变形中保留更高密度的位错和更小的晶粒结构,从而增强合金的高温强度。但Al_(3)(Sc,Zr)粒子的存在加剧了合金变形时的局部应力集中,导致合金伸长率降低。当拉伸温度不超过300℃时,复合添加微量Sc、Zr可以将Al-6.0Mg-0.4Mn合金的高温强度提高100 MPa左右,伸长率则有所减小。 展开更多
关键词 Al-6.0Mg-0.4Mn合金 Al_(3)(sc Zr)粒子 高温变形行为 力学性能
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Current development and prospect of national science and technology innovation platform in the railway industry 被引量:1
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作者 Fang Zhao Jinping Liu +3 位作者 Chunguang Zhang Zeping Zhao Xue Ning Junbiao Wang 《Railway Sciences》 2025年第2期266-279,共14页
Purpose–This study summarizes the overall situation of the resources of the national science and technology innovation platform in the railway industry,including the distribution of platform types,supporting institut... Purpose–This study summarizes the overall situation of the resources of the national science and technology innovation platform in the railway industry,including the distribution of platform types,supporting institutions,construction sites,professional fields,etc.,to provide a reference for the further improvement and optimization of the national science and technology innovation platform system in the railway industry.Design/methodology/approach–Through literature review,field investigation,expert consultation and other methods,this paper systematically investigates and analyzes the development status of the national science and technology innovation platform in the railway industry.Findings–Taking the national science and technology innovation platform of the railway industry as the research object,this paper investigates and analyzes the construction,development and distribution of the national science and technology innovation platform of railway industry over the years.And the National Engineering Research Center of High-speed Railway and Urban Rail Transit System Technology was taken as an example to introduce its operation effect.Originality/value–China Railway has made great development achievements,with the construction and development of national science and technology innovation platform in the railway industry.In recent years,a large number of national science and technology innovation platforms have been built in the railway industry,which play an important role in railway technological innovation,standard setting and commodification,and Railway Sciences provide strong support for railway technology development. 展开更多
关键词 Railway industry National science and technology innovation platform current development and prospect
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基于DR和VSC海上风电HVDC系统的并联运行控制
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作者 宁金叶 覃事刚 +1 位作者 徐谦 黄成菊 《电源学报》 北大核心 2026年第1期262-270,共9页
为了实现海上风力发电高比例友好消纳的目标,提出了1种基于二极管整流器DR(diode rectifier)高压直流HVDC(high-voltage direct current)输电系统和电压源换流器VSC(voltage source converter)HVDC输电系统并联运行的新型控制方法。这2... 为了实现海上风力发电高比例友好消纳的目标,提出了1种基于二极管整流器DR(diode rectifier)高压直流HVDC(high-voltage direct current)输电系统和电压源换流器VSC(voltage source converter)HVDC输电系统并联运行的新型控制方法。这2条线路均与海上风电场OWFs(offshore wind farms)连接,VSC-HVDC输电系统控制海上交流电网的电压和频率,即基于控制VSC-HVDC输电系统交流母线的有功功率平衡来控制OWFs的电压。当OWFs注入功率超过VSC-HVDC输电系统有功功率参考值时,OWFs电压升高,DR-HVDC输电系统激活,此时海上交流电网通过DR-HVDC线路传输OWFs所需的功率值,而系统频率由VSC-HVDC输电系统通过满足无功功率平衡来实现控制;当VSC-HVDC输电系统传输的功率与设定值相同时,DR-HVDC输电系统将自动关闭。所提方法的最大优点在于VSC-HVDC输电系统的容量仅用于支持系统正常运行,一旦OWFs投入运行,DR-HVDC输电系统将自动激活。最后,仿真结果验证了所提方法的有效性和优越性。 展开更多
关键词 海上风电场 高压直流 二极管整流单元 电压源变流器 频率控制 并联运行控制
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塔式太阳能SC-CO_(2)布雷顿循环三联产系统的设计与(火用)分析
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作者 郭富民 王成 +2 位作者 宫现辉 王刚 姜铁骝 《汽轮机技术》 北大核心 2026年第1期25-28,38,60,共6页
提出并研究了一种塔式太阳能驱动的超临界二氧化碳(SC-CO_(2))布雷顿循环和有机朗肯循环驱动制氢的三联产系统,其可实现电力、氢气和氧气的生产。借助太阳能塔式三联产(STRT)系统的热力仿真模型,对STRT系统的运行、(火用)和经济性能进... 提出并研究了一种塔式太阳能驱动的超临界二氧化碳(SC-CO_(2))布雷顿循环和有机朗肯循环驱动制氢的三联产系统,其可实现电力、氢气和氧气的生产。借助太阳能塔式三联产(STRT)系统的热力仿真模型,对STRT系统的运行、(火用)和经济性能进行了分析。结果表明,STRT系统的输出电功率和SC-CO_(2)布雷顿循环的循环效率分别为62.29MW和48.29%,有机朗肯循环的净输出功率和循环效率分别为8.02MW和16.35%,STRT系统的氢气和氧气生产速率分别为183.8kg/h和1 470.4kg/h,该系统在全年运行中展现出了稳定的运行性能。(火用)分析结果表明,STRT系统的总(火用)损为261.49MW,效率为25.0%。塔式接收器具有最大的(火用)损(218.85MW)。STRT系统的平准化电价和平准化氢价分别为0.764元/(kW·h)和约21.4元/kg,回收年限为11.31年,在理论上具有经济可行性。 展开更多
关键词 sc-CO_(2)布雷顿循环 塔式太阳能 三联产 有机朗肯循环 绿色能源制氢
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Numerical study of runaway current impact on sawtooth oscillations in tokamaks
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作者 Ruirui MA Chen ZHAO +1 位作者 Yao ZHOU Chang LIU 《Plasma Science and Technology》 2025年第3期10-21,共12页
This study investigates the influence of runaway current in runaway plasmas on the dynamics of sawtooth oscillations and resultant loss of runaway electrons(RE)using the 3D magnetohydrodynamic(MHD)code M3D-C^(1)(Jardi... This study investigates the influence of runaway current in runaway plasmas on the dynamics of sawtooth oscillations and resultant loss of runaway electrons(RE)using the 3D magnetohydrodynamic(MHD)code M3D-C^(1)(Jardin et al 2012 J.Comput.Sci.Discovery 6014002).Using an HL-2A-like equilibrium,we confirm that in the linear phase,the impact of REs on resistive internal kink instabilities is consistent with previous research.In the nonlinear phase,as the runaway current fully replaces the plasmas current,we observe a significant suppression of sawtooth oscillations,with the first sawtooth cycle occurring earlier compared to the case without runaway current.Following the first sawtooth collapse,plasma current density,runaway current density,and safety factor(q)flatten within the q=1 surface,albeit displaying fine structures.Subsequently,the growing high torodial(n)and poloidal(m)mode number modes disrupt the magnetic surfaces,leading to the loss of REs outside the q=1 surface,while minimally affecting the majority of REs well-confined within it.Thus,in the current model,the physical processes associated with the presence of sawtooth oscillations do not effectively dissipate runaway current,as REs are assumed to be collisionless.In addition,the final profile of runaway current density exhibits increased steepening near the q=1 surface in contrast to the initial profile,displaying a distinctive corrugated inhomogeneity influenced by the growing fluctuation of the n=0 component.Finally,detailed convergence tests are conducted to validate the numerical simulations. 展开更多
关键词 DISRUPTION runaway current sawtooth oscillations RE loss
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Therapeutic efficacy of transcranial direct current stimulation in treating auditory hallucinations in schizophrenia:A meta-analysis
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作者 Shi-Jia Zou Jin-Nan Shi 《World Journal of Psychiatry》 2025年第3期302-310,共9页
BACKGROUND Schizophrenia is a chronic psychiatric condition with complex symptomatology,including debilitating auditory hallucinations.Transcranial direct current stimulation(tDCS)has been explored as an adjunctive tr... BACKGROUND Schizophrenia is a chronic psychiatric condition with complex symptomatology,including debilitating auditory hallucinations.Transcranial direct current stimulation(tDCS)has been explored as an adjunctive treatment to alleviate such symptoms.AIM To evaluate the therapeutic efficacy of tDCS in schizophrenia.METHODS Adhering to PRISMA guidelines,we systematically searched PubMed,Embase,Web of Science,and the Cochrane Library on September 19,2023,for randomized controlled trials examining the efficacy of tDCS in schizophrenia,with no language or time restrictions.We included studies that compared tDCS with a control condition and reported clinically relevant outcomes.Data extraction and quality assessments were performed by independent evaluators using the Cochrane Collaboration's risk of bias tool.Statistical heterogeneity was evaluated,and a random-effects model was applied due to moderate heterogeneity(I2=41.3%).RESULTS Nine studies comprising 425 participants(tDCS group:219,control group:206)were included.The meta-analysis demonstrated a significant reduction in auditory hallucination scores following tDCS treatment(weighted mean difference:-2.18,95%confidence interval:-4.0 to-0.29,P<0.01).Sensitivity analysis confirmed the robustness of the results,with no significant influence from individual studies.Additionally,publication bias was not detected,supporting the reliability and generalizability of the findings.These results underscore the efficacy of tDCS as a therapeutic intervention for auditory hallucinations in schizophrenia.CONCLUSION tDCS significantly reduces auditory hallucinations in schizophrenia,suggesting its potential as an effective adjunctive treatment for managing this disabling symptom.The findings highlight the practical significance of tDCS in clinical settings,particularly for patients with treatment-resistant auditory hallucinations. 展开更多
关键词 scHIZOPHRENIA Transcranial direct current stimulation Auditory hallucinations META-ANALYSIS
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Short-term effects of transcranial direct current stimulation on pain sensitivity, emotional and cognitive processes in non-suicidal self-injury: a randomised controlled trial
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作者 Chang Lei Diyang Qu +4 位作者 Dennis Chong Yangyang Yi Weijian Wu Yiheng Tu Runsen Chen 《General Psychiatry》 2025年第3期176-185,共10页
Background Pain sensitivity is critical for preventing non-suicidal self-injury(NSSI)behaviours;however,individuals engaging in such behaviours often exhibit decreased pain sensitivity,which may undermine this natural... Background Pain sensitivity is critical for preventing non-suicidal self-injury(NSSI)behaviours;however,individuals engaging in such behaviours often exhibit decreased pain sensitivity,which may undermine this natural safeguard.The dorsolateral prefrontal cortex(DLPFC)is a key region involved in pain regulation,and recent approaches using transcranial direct current stimulation(tDCS)to target the DLPFC have shown potential for modulating pain processing and restoring normal pain perception for individuals engaging in NSSI behaviours.Aims This study aimed to explore the immediate and short-term effects of a single session of tDCS on pain sensitivity in individuals with NSSI,as well as its secondary effects on mood and NSSI-related factors.Methods In this randomised,double-blind,parallel,sham-controlled clinical trial,participants with a history of NSSI were randomly assigned to receive either active or sham tDCS.The intervention consisted of a single 20 min tDCS session targeting the left DLPFC.The primary outcome was pain sensitivity,measured by the pressure pain threshold(PPT)and heat pain score(HPS).Secondary and additional outcomes included NSSI urges,NSSI resistance,self-efficacy in resisting NSSI,mood-related variables and exploratory cognitive-affective processes such as rumination,self-criticism and self-perceived pain sensitivity,assessed at baseline,immediately post-intervention,and at 24 hours,1 week and 2 weeks follow-ups.Results For the primary outcomes,no significant differences between groups were observed for pain sensitivity(PPT,padj=0.812;HPS,padj=0.608).However,an exploratory sensitivity analysis treating each trial as an individual observation revealed a significant effect on HPS(padj=0.036).For the secondary and additional outcomes,although there were initial improvements in joyful feelings and reductions in negative affect at 2 weeks post-intervention,these effects did not remain significant after multiple comparison corrections.Notably,reductions in rumination were statistically significant at both 1-week and 2-week follow-ups(1 week,p_(adj)=0.040;2 weeks,p_(adj)=0.042).There were no significant effects on NSSI urges,NSSI resistance,self-efficacy in resisting NSSI or self-criticism.Conclusions A single session of tDCS over the left DLPFC did not produce significant changes in pain sensitivity in individuals with NSSI.A sensitivity analysis indicated an effect on heat pain sensitivity,possibly reflecting changes in brain activity,warranting confirmation through neuroimaging.These findings suggest that tDCS warrants further investigation for its potential to influence pain-related cognitive-affective processes in individuals with NSSI. 展开更多
关键词 Non Suicidal Self Injury MOOD Dorsolateral Prefrontal Cortex modulating pain processing Transcranial Direct current Stimulation Cognitive Processes dorsolateral prefrontal cortex dlpfc transcranial direct current stimulation tdcs
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Luminescent target interactions in ICP discharges:a diagnostic method for plasma current density
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作者 Zhe ZHANG Lujia ZHANG +4 位作者 Huibin ZHENG Jiayun QI Zun ZHANG Xiangyang LIU Haibin TANG 《Plasma Science and Technology》 2025年第6期59-68,共10页
Recently,it has been observed that during the operation of an inductively coupled plasma(ICP),a luminescent target(BAM,BaMgAl10O17:Eu)can interact with the plasma beam and emit blue light.After excluding the influence... Recently,it has been observed that during the operation of an inductively coupled plasma(ICP),a luminescent target(BAM,BaMgAl10O17:Eu)can interact with the plasma beam and emit blue light.After excluding the influence of ultraviolet(UV)and electromagnetic wave radiation,the results indicate that the BAM target may undergo luminescent excitation due to collisions with electrons and ions.This led us to investigate the physical mechanism behind this plasma luminescence excitation phenomenon.A spectrometer was used to record the luminescent spectroscopy and peak light intensity.Under excitation by argon plasma,the BAM material emits a continuum spectrum from 400 nm to 550 nm,with the peak light intensity located at 462.58 nm,which is the same as the spectrum excited by UV torchlight.To identify the relationship between the plasma parameters and the luminescent intensity,Langmuir and Faraday probes were employed to determine the local plasma parameters such as electron density,electron temperature,and current density.After normalizing the peak light intensity to the plasma parameters,the most interesting point is that the current density is linearly correlated with the luminescent light intensity.To verify the repeatability and lifetime of the plasma-luminescence interaction,a 600 s lifetime test was conducted in a 200 W ICP discharge environment.The maximum difference for the peak light strength of the luminescent spectrum is 6.5%.From a voltage bias experiment and a theoretical derivation,we initially identified that bombardment by ions plays the dominant role in the luminescence excitation process,which also explains the mechanism by which the current density is proportional to the luminescence intensity.This new finding leads us to reconsider the possibility of applying this plasma luminescence phenomenon to optical plasma diagnostics.The BAM light intensity can potentially be used to predict the current density of a plasma beam for large-area two-dimensional(2D)measurements and can capture high spatial resolution in a single test.We believe that this method may lead to high-efficiency,spatially resolved plasma current density measurement. 展开更多
关键词 inductively coupled plasma plasma-luminescence excitation current density luminescence intensity
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Terahertz time-domain spectroscopy to probe laser-excited spin currents in a Co/Gd system
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作者 Fan Zhang Bin Hong +6 位作者 Michel Hehn Rongqing Zhao Gregory Malinowski Yong Xu Stéphane Mangin Jon Gorchon Weisheng Zhao 《Chinese Physics B》 2025年第12期388-392,共5页
Single shot all-optical switching of the magnetization by femtosecond laser pulses in rare-earth transition-metal ferrimagnetic materials is particularly promising for future ultrafast magnetic storage applications.Mo... Single shot all-optical switching of the magnetization by femtosecond laser pulses in rare-earth transition-metal ferrimagnetic materials is particularly promising for future ultrafast magnetic storage applications.Moreover,ultrafast lasergenerated spin currents appear to play an important role in the switching process.Here,we try to separately detect the spin current from Gd in a Co/Gd bilayer system using terahertz time-domain spectroscopy.To this aim,we use different capping,buffer and embedded layers in order to tune the spin-to-charge and spin-current propagation and identify currents from each of the layers.We attribute the observed THz emission in all layers to the transition metal demagnetization induced spin currents,and detect no contribution from the Gd demagnetization.We attribute this absence of Gd-induced THz signal to the potentially slow demagnetization of Gd,which shift the emission spectra to lower frequencies,below our detection capabilities.These results highlight the limitations in using materials suffering from the so-called critical slowdown for the optimization of spintronic THz emitters. 展开更多
关键词 Co/Gd bilayer spin current THz emission DEMAGNETIZATION
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Multi-Scale Time Series Segmentation Network Based on Eddy Current Testing for Detecting Surface Metal Defects
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作者 Xiaorui Li Xiaojuan Ban +6 位作者 Haoran Qiao Zhaolin Yuan Hong-Ning Dai Chao Yao Yu Guo Mohammad S.Obaidat George Q.Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期528-538,共11页
In high-risk industrial environments like nuclear power plants,precise defect identification and localization are essential for maintaining production stability and safety.However,the complexity of such a harsh enviro... In high-risk industrial environments like nuclear power plants,precise defect identification and localization are essential for maintaining production stability and safety.However,the complexity of such a harsh environment leads to significant variations in the shape and size of the defects.To address this challenge,we propose the multivariate time series segmentation network(MSSN),which adopts a multiscale convolutional network with multi-stage and depth-separable convolutions for efficient feature extraction through variable-length templates.To tackle the classification difficulty caused by structural signal variance,MSSN employs logarithmic normalization to adjust instance distributions.Furthermore,it integrates classification with smoothing loss functions to accurately identify defect segments amid similar structural and defect signal subsequences.Our algorithm evaluated on both the Mackey-Glass dataset and industrial dataset achieves over 95%localization and demonstrates the capture capability on the synthetic dataset.In a nuclear plant's heat transfer tube dataset,it captures 90%of defect instances with75%middle localization F1 score. 展开更多
关键词 Eddy current testing nondestructive testing semantic segmentation time series analysis
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Effect of preoperative transcranial direct current stimulation on postoperative delirium in elderly patients following laparoscopic surgery
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作者 Xi Yang Yu-Fei Wei +4 位作者 Chen-Hui Ye Wen-Di Tian Xue-Yao Li Ye-Ju Hu Li-Ping Chen 《World Journal of Psychiatry》 2025年第10期239-249,共11页
BACKGROUND Postoperative delirium(POD),an acute neuropsychiatric complication in elderly surgical patients,manifests as attention and cognitive disturbances that may last 24-72 hours after surgery,potentially progress... BACKGROUND Postoperative delirium(POD),an acute neuropsychiatric complication in elderly surgical patients,manifests as attention and cognitive disturbances that may last 24-72 hours after surgery,potentially progressing to dementia.Transcranial direct current stimulation(tDCS),a non-invasive neuromodulation technique,enhances cortical excitability and cognitive function by modulating brain networks and synaptic plasticity.Elderly patients undergoing major laparoscopic surgery face elevated POD risks due to prolonged anesthesia and pneumoperitoneum-induced cerebral hypoperfusion.This study investigates whether pre-anesthesia tDCS can reduce POD incidence in this population.AIM To investigate the effect of preoperative tDCS on reducing the incidence of POD in elderly patients undergoing major laparoscopic surgery.METHODS In this study,we enrolled 220 elderly patients who underwent major laparoscopic surgery between April 2024 and December 2024.Patients were randomly assigned to the active-tDCS(group A)and sham-tDCS(group S)groups.A single session of tDCS or sham stimulation was administered 30 minutes before anesthesia induction.The primary outcome was the incidence of POD during within 3 days postoperatively.RESULTS A total of 201 patients were included in the final analysis,with 100 patients in group A and 101 in group S.The incidence of POD within 3 days postoperatively was 7.0%in group A,which was significantly lower than 22.8%in group S.On postoperative day 1,the Self-Rating Anxiety Scale and Self-Rating Depression Scale scores significantly differed between the two groups,but the pain scores showed no significant difference.CONCLUSION A single session of preoperative tDCS can reduce the incidence of POD in elderly patients undergoing major laparoscopic surgery and can also reduce postoperative anxiety and depression in these patients. 展开更多
关键词 Transcranial direct current stimulation Postoperative delirium COGNITION Laparoscopic surgery Randomized controlled trial
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Effect of theta-transcranial alternating current stimulation on working memory performance among healthy adults:A systematic review and meta-analysis
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作者 Tian-Ya Hou Xiao-Fei Mao Rui-Ke Zhang 《World Journal of Psychiatry》 2025年第9期328-341,共14页
BACKGROUND Working memory serves as a fundamental cognitive function that substantially impacts performance in various cognitive tasks.Extensive neurophysiological research has established that theta oscillations(4-8 ... BACKGROUND Working memory serves as a fundamental cognitive function that substantially impacts performance in various cognitive tasks.Extensive neurophysiological research has established that theta oscillations(4-8 Hz)play an essential role in supporting working memory operations.Theta-band transcranial alternating current stimulation(tACS)offers a potential mechanism for working memory enhancement through direct modulation of these fundamental neural oscillations.Nevertheless,current empirical evidence shows substantial variability in the observed effects of theta-tACS across studies.AIM To conduct a systematic review and meta-analysis evaluating the effects of thetatACS on working memory performance in healthy adults.METHODS A systematic literature search was performed on PubMed,EMBASE,and Web of Science up to March 10,2025.Effect sizes were computed using Hedges’g with 95%confidence intervals(CIs),with separate meta-analyses for all included studies and for distinct working memory paradigms[n-back and delayed matchto-sample(DMTS)tasks]to examine potential task-specific effects.Subgroup analyses and meta-regression were performed to evaluate the influence of key moderating variables.RESULTS The systematic review included 21 studies(67 effect sizes).Initial meta-analysis showed theta-tACS moderately improved working memory(Hedges’g=0.405,95%CI:0.212-0.598).However,this effect became nonsignificant after correcting for publication bias(trim-and-fill adjusted Hedges’g=0.082,95%CI:-0.052 to 0.217).Task-specific analyses revealed significant benefits in n-back tasks(Hedges’g=0.463,95%CI:0.193-0.733)but not in DMTS tasks(Hedges’g=0.257,95%CI:-0.186 to 0.553).Moderator analyses showed that performance in n-back tasks was influenced by stimulation frequency(P=0.001),concurrent status(P=0.014),task modality(P=0.005),and duration(P=0.013),whereas only the region of targeted stimulation(P=0.012)moderated DMTS tasks.CONCLUSION Theta-tACS enhances working memory in healthy adults,with effects modulated by the task type and protocol parameters,offering dual implications for cognitive enhancement and clinical interventions. 展开更多
关键词 Working memory Transcranial alternating current stimulation THETA Healthy adults N-BACK Delayed match-tosample task
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Current density in anomalous Hall effect regime under weak scattering
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作者 Ning Dai Bin Zhou 《Chinese Physics B》 2025年第7期524-532,共9页
A finite equilibrium current density arises in the anomalous Hall effect(AHE)as a result of time-reversal symmetry breaking,affecting both the differential current density and total current.In this paper,we illustrate... A finite equilibrium current density arises in the anomalous Hall effect(AHE)as a result of time-reversal symmetry breaking,affecting both the differential current density and total current.In this paper,we illustrate the equilibrium current density in a ribbon-shaped system within the AHE regime,consisting of two sets of counterpropagating channels arranged in a zebra stripes pattern.While the middle channels are susceptible to scattering,the edge channels remain relatively robust.Despite this difference,all channels exhibit the same differential current density when subjected to a differential voltage across the two ends of the ribbon.When a differential voltage is applied to both sides of the ribbon,it results in a snaking pattern of differential current density forming across it.Furthermore,in a four-terminal device comprising the ribbon and two normal leads,it is found that Hall conductance is independent of ribbon width within certain scattering strengths due to the differences in robustness between middle and edge channels.These findings disclose the details of the AHE transport in a finite-sized system under weak scattering. 展开更多
关键词 anomalous Hall effect quantum transport current density non-equilibrium Green’s function
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Low-Density Pulsed Current Induced Refinement of Secondary α Phase for Strengthening Ti-6Al-4V-0.5Mo-0.5Zr Alloy Without Sacrificing Ductility
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作者 Tu Yanni Luo Wei +2 位作者 Liu Huiqun Feng Weizhong Zhang Pinghui 《稀有金属材料与工程》 北大核心 2026年第1期78-91,共14页
Low-density short-duration pulsed current-assisted aging treatment was applied to the Ti-6Al-4V-0.5Mo-0.5Zr alloy subjected to different solution treatments.The results show that numerous α_(p) phases redissolve into... Low-density short-duration pulsed current-assisted aging treatment was applied to the Ti-6Al-4V-0.5Mo-0.5Zr alloy subjected to different solution treatments.The results show that numerous α_(p) phases redissolve into the new β phase during the pulsed current-assisted aging process,and then the newly formed β phase is mainly transformed into the β_(t) phase,with occasional transition to new α_(p) phase,leading to a remarkable grain refinement,especially for the lamellarαs phases.In comparison to conventional aging treatment,the pulsed current-assisted aging approach achieves a significant enhancement in strength without degrading ductility,yielding an excellent mechanical property combination:a yield strength of 932 MPa,a tensile strength of 1042 MPa,and an elongation of 12.2%.It is primarily ascribed to the increased fraction of β_(t) phases,the obvious grain refinement effect,and the slip block effect induced by the multiple-variantαs colonies distributed within β_(t) phases. 展开更多
关键词 titanium alloy pulsed current microstructure refinement strength DUCTILITY
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Comment on‘Variable viscosity effects on the flow of MHD hybrid nanofluid containing dust particles over a needle with Hall current-a Xue model exploration’
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作者 Asterios Pantokratoras 《Communications in Theoretical Physics》 2025年第10期209-210,共2页
1st error Within the abstract of the above paper,in the mathematical modeling,in Table 1 and in the concluding remarks,it is clearly mentioned that the base fluid in[1]is engine oil and ALL results have been produced ... 1st error Within the abstract of the above paper,in the mathematical modeling,in Table 1 and in the concluding remarks,it is clearly mentioned that the base fluid in[1]is engine oil and ALL results have been produced for Prandtl number Pr=6.2. 展开更多
关键词 dust particles mathematical modeling mathematical modelingin variable viscosity NEEDLE magnetic field hybrid nanofluid Hall current
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Correction:Impact of twice-a-day transcranial direct current stimulation interuention on cognitive function and motor cortex plasticity in patients with Alzheimer's disease
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《General Psychiatry》 2025年第5期415-415,共1页
An unauthorised version of the Chinese MMSE was used in this article by the authors without permission from the copyright owner,PAR.Necessary permission has now been retrospectively obtained from PAR.The MMSE is a cop... An unauthorised version of the Chinese MMSE was used in this article by the authors without permission from the copyright owner,PAR.Necessary permission has now been retrospectively obtained from PAR.The MMSE is a copyrighted instrument and may not be used or reproduced in whole or in part,in any form or language,or by any means without the written permission of PAR(www.parinc.com). 展开更多
关键词 transcranial direct current stimulation motor cortex plasticity COPYRIGHT cognitive function retrospective permission unauthorized version alzheimer's disease
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