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Chinese Physics B 2017年第2期26卷 194-199页

作者： Xiao-Long Fu Guo-Cheng Wu wei-xiong bai Guang-Ming Wang Jian-Gang Liang Air and Missile Defense College Air Force Engineering University Xi＇ an 710051 China

In this paper, an ultra-compact single negative（SNG） electric waveguided metamaterial（WG-MTM） is first investigated and used to reduce the mutual coupling in E ＆ H planes of a dual-band microstrip antenna array. The proposed SNG electric WG-MTM unit cell is designed by etching two different symmetrical spiral lines on the ground, and has two stopbands operating at 1.86 GHz and 2.40 GHz. The circuit size is very compact, which is only λ_0/33.6 ×λ_0/15.1（where λ_0 is the wavelength at 1.86 GHz in free space）. Taking advantage of the dual-stopband property of the proposed SNG electric WG-MTM, a dual-band microstrip antenna array operating at 1.86 GHz and 2.40 GHz with very low mutual coupling is designed by embedding a cross shaped array of the proposed SNG electric WG-MTM. The measured and simulated results of the designed dual-band antenna array are in good agreement with each other, indicating that the mutual coupling of the fabricated dual-band antenna array realizes 9.8/11.1 d B reductions in the H plane, 8.5/7.9 d B reductions in the E plane at1.86 GHz and 2.40 GHz, respectively. Besides, the distance of the antenna elements in the array is only 0.35 λ_0（where λ_0 is the wavelength at 1.86 GHz in free space）. The proposed strategy is used for the first time to reduce the mutual coupling in E ＆ H planes of the dual-band microstrip antenna array by using ultra-compact SNG electric WG-MTM.

关键词： waveguided metamaterial(WG-MTM) dual-band microstrip antenna array mutual coupling reduction ultra-compact circuit size

Metamaterial beam scanning leaky-wave antenna based on quarter mode substrate integrated waveguide structure

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Chinese Physics B 2017年第2期26卷 200-205页

作者： Guo-Cheng Wu Guang-Ming Wang Xiao-Long Fu Jian-Gang Liang wei-xiong bai Air and Missile Defense College Air Force Engineering University Xi＇an 710051 China

In this paper, we first propose a metamaterial structure by etching the same two interdigital fingers on the upper ground of quarter mode substrate integrated waveguide（QMSIW）. The simulated results show that the proposed QMSIWbased metamaterial has a continuous phase constant changing from negative to positive values within its passband. A periodic leaky-wave antenna（LWA）, which consists of 11 QMSIW-based metamaterial unit cells, is designed, fabricated,and measured. The measured results show that the fabricated antenna achieves a continuous beam scanning property from backward-43° to forward ＋32° over an operating frequencyrange of 8.9 GHz–11.8 GHz with return loss better than 10 d *** measured antenna gain keeps consistent with the variation of less than 2 d B over the operating frequency range with a maximum gain of 12 d B. Besides, the measured and simulated results are in good agreement with each other, indicating the significance and effectiveness of this method.

关键词： metamaterial leaky-wave antenna quarter mode substrate integrated waveguide(QMSIW) continuous beam scanning property

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang Zeng wei Tan Xingxing Chen Shuyuan bai Qiong Wu Yushan Chen Zhen wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： wei xiong Xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Adaptive-basis decomposition-based low-rank network for efficient non-uniform motion deblurring

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Optoelectronics Letters 2025年第1期21卷 43-50页

作者： CHEN Lei xiong Qingbo ZHANG wei LI Runde School of Software Henan University School of Applied Technology China University of Labor Relations

In this study, we present a unified sparsity-driven framework that significantly enhances motion deblurring performance by integrating two key components: a custom-designed dataset and a low-rank module(LRM). This framework leverages the inherent sparsity of per-pixel blur kernels to bolster both deblurring accuracy and model interpretability. Firstly, we propose an adaptive-basis decomposition-based deblurring(ADD) approach, which constructs a tailored training dataset to enhance the generalization capacity of the deblurring network. The ADD framework adaptively decomposes motion blur into sparse basis elements, effectively addressing the intricacies associated with non-uniform blurs. Secondly, an LRM is proposed to improve the interpretability of deblurring models as a plug-and-play module, primarily designed to identify and harness the intrinsic sparse features in sharp images. A series of ablation studies have been conducted to substantiate the synergistic advantages of combining the proposed ADD with the LRM for overall improvement in deblurring efficacy. Subsequently, we empirically demonstrate through rigorous experimentation that incorporating the LRM into an existing Uformer network leads to substantial enhancement in reconstruction performance. This integration yields a sparsity-guided low-rank network(SGLRN). Operating under the overarching principle of sparsity, SGLRN consistently outperforms state-of-the-art methods across multiple standard deblurring benchmarks. Comprehensive experimental results, assessed through quantitative metrics and qualitative visual evaluations, provide compelling evidence of its effectiveness. The overall deblurring results are available at Google Drive.

关键词： Image enhancement

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia Zheng Hongming bai Jia-Sheng Rao Guiyun Song wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles

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Neural Regeneration Research 2025年第4期20卷 1124-1134页

作者： Yanting Liu wei Huang Jiayi Wen Xin xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li weili Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong-Hongkong-Macao CNS Regeneration Institute of Jinan UniversityJinan UniversityGuangzhouGuangdong ProvinceChina

The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal ***,it remains largely unclear how PINK1 and Parkin are expressed in mammalian *** has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small *** this issue is critical for elucidating the in vivo roles of PINK1 and ***,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate *** the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate *** found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey ***1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable *** double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial *** findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage.

关键词： neurodegeneration Parkin Parkinson’s disease PINK1 subcellular distribution

稀土元素Er、Yb和Y掺杂ZrO_(2)的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 156-162页

作者：熊威任浩重庆交通大学航空学院重庆402247 重庆交通大学绿色航空技术研究院重庆401147

氧化锆具有声子能量低,介电常数高和带隙较宽等优良特性,并且立方相的氧化锆(cZrO_(2))透光率高,适合作为上转换发光材料的基质.采用基于密度泛函理论(DFT)的第一性原理平面波赝势法研究了稀土元素Er、Yb和Y掺杂cZrO_(2)的电子结构和光... 详细信息

氧化锆具有声子能量低,介电常数高和带隙较宽等优良特性,并且立方相的氧化锆(cZrO_(2))透光率高,适合作为上转换发光材料的基质.采用基于密度泛函理论(DFT)的第一性原理平面波赝势法研究了稀土元素Er、Yb和Y掺杂cZrO_(2)的电子结构和光学性质.计算结果显示,掺入Y元素后,cZrO_(2)转变为直接带隙材料,继续掺入Er和Yb原子后,费米能级移动到价带内,带隙显著减小.Y和Er混掺后,增强了cZrO_(2)在近红外波段的吸收能力.继续掺入Yb后,cZrO_(2)对近红外波段的吸收能力有了进一步地增加.

关键词：氧化锆第一性原理电子结构光学性质

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百草枯中毒进行性肺损害HRCT表现与临床预后的关系

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延安大学学报（医学科学版） 2016年第4期14卷 50-52页

作者：刘强王剑韩炜闫雄伟白光明李塞玲安塞县人民医院陕西安塞717400 延安大学附属医院影像科陕西延安716000 甘泉县人民医院影像科陕西甘泉716100

目的探讨百草枯中毒进行性肺损害HRCT表现与临床预后的关系。方法结合相关文献,回顾性分析5例百草枯中毒死亡病例的临床及进行性肺损害HRCT表现。结果中毒早期（1~7 d）HRCT表现肺纹理增粗、紊乱、模糊,局部肺叶透光度减低,胸膜下见磨... 详细信息

目的探讨百草枯中毒进行性肺损害HRCT表现与临床预后的关系。方法结合相关文献,回顾性分析5例百草枯中毒死亡病例的临床及进行性肺损害HRCT表现。结果中毒早期（1~7 d）HRCT表现肺纹理增粗、紊乱、模糊,局部肺叶透光度减低,胸膜下见磨玻璃影及少许实变影。中毒中期（8~14 d）HRCT表现肺纹理进行性增粗、紊乱,磨玻璃影及实变影范围增大,气胸、纵膈及胸壁皮下气肿。中毒后期（≥15 d）HRCT表现肺实质性病变、肺间质性病变、支气管扩张、胸腔积液伴肝脾肾肿大。结论百草枯中毒进行性肺损害HRCT表现与临床病情发展转归具有一致性,对临床治疗和预后判断有很高的应用价值。

关键词：百草枯中毒肺损害 HRCT

Temperature effect on buckling properties of ultra-thin-walled lenticular collapsible composite tube subjected to axial compression

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Chinese Journal of Aeronautics 2014年第5期27卷 1312-1317页

作者： bai Jiangbo xiong Junjiang School of Transportation Science and Engineering Beihang University

This paper seeks to outline the temperature effect on the buckling properties of ultra-thin-walled lenticular collapsible composite tube（LCCT） subjected to axial *** buckling tests of the LCCT specimens subjected to axial compression were carried out on INSTRON-500 N servo-hydraulic machine in dry state and at the temperatures of 25 C, 100 C and 80 C. The load–displacement curves and buckling initiation loads were measured and the buckling initiation mechanism was discussed from experimental observations. Experiments show that the buckling initiation load, on average, is only about 2.2% greater at the low temperature of 80 C than at the room temperature of 25 C due to the material hardening, demonstrating an insignificant increase in the buckling initiation load, whereas it is about 19.5% lower at the high temperature of 100 C than at the room temperature owing to the material softening, implying a significant decrease in the buckling initiation load. The failure mode of the LCCT in axial compression tests at three different temperatures can be reckoned to be characteristic of the buckling initiation and propagation around the central region until rupture. The finite element（FE） model is presented to simulate the buckling initiation mechanism based on the eigenvalue-based methodology. Good correlation between experimental and numerical results is achieved.

关键词： Axial compression Buckling Composite Finite element analysis Lenticular collapsible tube