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Controllable Optical Bistability in a Crystal of Molecular Magnets System

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Communications in Theoretical Physics 2008年第10期50卷 1003-1008页

作者： liu Ji-Bing LU Xin-You HAO Xiang-Ying si liu-gang YANG Xiao-Xue Department of Physics Hubei Normal University Huangshi 435002 China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We investigate the formation of optical bistability （OB） in a crystal of molecular magnets contained in a unidirectional ring cavity. The crystal is subjected to one dc magnetic field and two （probe and coupling） ac resonant magnetic field. The results show that OB can be controlled efficiently by adjusting the intensity of the control field, the detuning of probe magnetic field and the cooperation parameter, Furthermore, within certain parameter range, the optical multistablity （OM） can also be observed in the crystal medimn. This＇ investigation can be used for designing new types of nonelectronic devices for realizing switching process.

关键词： optical bistability molecular magnets cooperation parameter

Ultraslow Optical Solitons in a Coupled Double Quantum-Well Nanostructure

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Communications in Theoretical Physics 2009年第3期51卷 519-523页

作者： HAO Xiang-Ying liu Ji-Bing LU Xin-You SONG Pei-Jun si liu-gang Physics Department Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Hubei Normal University Huangshi 435002 China

We demonstrate the formation of ultraslow dark semiconductor double quantum well （SDQW） structure based optical solitons with a four-level scheme in an asymmetric on intersubband transitions by using only a low-intensity pulsed laser radiation. With appropriate conditions we show numerically that the dark optical soliton can travel with a ultraslow group velocity Vg/c - -10^-3. Such a semiconductor system is much more practical than its atomic counterpart because of its flexible design and the controllable interference strength. This nonlinear optical process in the SDQW solid-state material may be used for the control technology of optical delay lines and optical buffers.

关键词： optical solitons intersubband transitions semiconductor quantum well

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大型住宅小区项目管理分析

工程建设与设计 2019年第22期 241-242页

作者：刘思刚克拉玛依市保障性住房投资建设管理有限责任公司

在现代化社会的快速发展中,我国建筑工程项目的建设规模在不断扩大,并且具有施工难度大、施工周期长、参与项目建设人数多等特点,因此,在建设施工和管理过程中存在很多风险因素。为了确保工程项目建设的顺利实施,建设企业需要引进更多... 详细信息

在现代化社会的快速发展中,我国建筑工程项目的建设规模在不断扩大,并且具有施工难度大、施工周期长、参与项目建设人数多等特点,因此,在建设施工和管理过程中存在很多风险因素。为了确保工程项目建设的顺利实施,建设企业需要引进更多先进的管理技术和管理方法,提高项目建设的整体质量,满足环保、成本、节能等要求。基于此,论文结合住宅小区实例,研究了大型住宅小区项目管理的相关内容。

关键词：大型住宅小区项目管理优化措施

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu si Wang Weiqi Zhang Jing Qu Guang-Hui liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou Ying Xiaoli si Naijia Xue Yi liu Ran Zheng Ying Chen Jiali Pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

科学数据伦理治理:政策框架与路径——以英国为例

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现代情报 2025年第1期45卷 112-123,134页

作者：刘先瑞司莉武汉大学信息管理学院湖北武汉430072

[目的/意义]完善科学数据伦理治理有助于规范科学数据收集、共享和使用,发挥数据作为科研的关键资源与要素的功能,优化科学数据管理服务。[方法/过程]本研究基于扎根理论分析英国科学数据伦理政策,总结其政策框架与内容,并通过矩阵编码... 详细信息

[目的/意义]完善科学数据伦理治理有助于规范科学数据收集、共享和使用,发挥数据作为科研的关键资源与要素的功能,优化科学数据管理服务。[方法/过程]本研究基于扎根理论分析英国科学数据伦理政策,总结其政策框架与内容,并通过矩阵编码与社会网络分析方法揭示治理特征,提出我国优化科学数据伦理治理的建议。[结果/结论]研究发现,伦理政策框架包括治理环境、主体与策略3层面。伦理治理环境内容分为适用领域、适用主体、概念定义、问题分析与现有政策;伦理治理主体内容涉及治理主体界定与促进主体协作;伦理治理策略内容涵盖治理指导与各阶段治理措施。其治理特征有3维度:注重定义概念,明确分配主体权责与促进协作,全面厘定治理策略与加强伦理风险防控。据此提出4条治理路径:形成治理体系,规范治理理论,明确各方权责与协作方式,细化各阶段治理措施。

关键词：科学数据数据伦理数据治理政策分析英国

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基于特征增强和样本充分学习的红外飞机检测

电光与控制 2025年第1期32卷 54-60页

作者：徐红鹏刘刚司起峰陈会祥河南科技大学信息工程学院河南洛阳471000

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取... 详细信息

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取网络对目标特征的提取能力。通过在Focal Loss中添加调制因子,在关注难负样本学习的基础上,充分利用包含目标特性的部分易负样本,使得样本充分学习,从而帮助检测算法学习到更有意义的目标特征。实验表明,所提算法在自制红外飞机数据集上的mAP_(50)达到96.9%,能够有效实现红外飞机目标检测。

关键词：红外飞机检测全局上下文空间注意力 Focal Loss 易负样本

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Challenges in the management of visual and tactile hallucinations in elderly people

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World Journal of Psychiatry 2025年第1期15卷 185-188页

作者： si-Sheng Huang Division of Geriatric Psychiatry Department of PsychiatryChanghua Christian HospitalChanghua 500Taiwan Department of Post-Baccalaureate Medicine College of MedicineNational Chung Hsing UniversityTaichung 402Taiwan

This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly *** discussion addresses differential diagnoses and potential underlying mechanisms,as well as the psychopathology associated with tactile hallucinations,and emphasizes the necessity for invest-igation into the possibility of coexisting delusional infestation(parasitosis).These symptoms frequently manifest in patients with primary psychotic disorders,organic mental disorders,and substance use *** proposed pathophy-siological mechanisms may involve dopaminergic imbalances and dysfunction of the striatal dopamine transporter.

关键词： Delusional infestation Dementia Haptic hallucination Scratching behavior Tactile hallucination Visual hallucination Alzheimer’s disease

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)Alsi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-si alloy,we used Alsi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment