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基于位置服务模型的高速列车二等车厢布置改进设计

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机械设计 2017年第9期34卷 115-118页

作者：章勇支锦亦刘峰梁刚毅西南交通大学人机环境系统设计研究所四川成都610031 湖南工程学院设计艺术学院湖南湘潭411104

高速列车市场效益除采用更高的平均速度和更多的运营次数,提高空间利用率也是较为有效的手段,以此降低高速列车运营成本。位置服务能为高速列车二等车厢的座椅布置网络提供一种新的布置方法,不仅能提高高速列车二等车厢的座位数或平均... 详细信息

高速列车市场效益除采用更高的平均速度和更多的运营次数,提高空间利用率也是较为有效的手段,以此降低高速列车运营成本。位置服务能为高速列车二等车厢的座椅布置网络提供一种新的布置方法,不仅能提高高速列车二等车厢的座位数或平均负载系数,还能生成一个节省空间的车厢布置模型,设计人员可依据高速列车二等车厢布置的尺寸范围和实际情况,利用布置模型生成基于位置服务(LBS)的车厢布置设计方案。针对高速列车二等车厢采用位置服务模型的布置策略,提出了新的布置方法。结果表明:新的车厢布置可降低运营成本,提高运营效率。

关键词：高速列车二等车厢位置服务模型布置模型改进设计

Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： yi liu JiuHou Lei FuQing Huang Su Zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

Advances in the Development of Gradient Scaffolds Made of Nano‑Micromaterials for Musculoskeletal Tissue Regeneration

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Nano-Micro Letters 2025年第3期17卷 455-500页

作者： Lei Fang Xiaoqi Lin Ruian Xu Lu liu Yu Zhang feng Tian Jiao Jiao Li Jiajia Xue Beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China School of Biomedical Engineering Faculty of Engineering and ITUniversity of Technology SydneySydneyNSW 2007Australia

The intricate hierarchical structure of musculoskeletal tissues,including bone and interface tissues,necessitates the use of complex scaffold designs and material structures to serve as tissue-engineered *** has led to growing interest in the development of gradient bone scaffolds with hierarchical structures mimicking the extracellular matrix of native tissues to achieve improved therapeutic *** on the anatomical characteristics of bone and interfacial tissues,this review provides a summary of current strategies used to design and fabricate biomimetic gradient scaffolds for repairing musculoskeletal tissues,specifically focusing on methods used to construct compositional and structural gradients within the *** latest applications of gradient scaffolds for the regeneration of bone,osteochondral,and tendon-to-bone interfaces are ***,the current progress of testing gradient scaffolds in physiologically relevant animal models of skeletal repair is discussed,as well as the challenges and prospects of moving these scaffolds into clinical application for treating musculoskeletal injuries.

关键词： Gradient scaffolds Musculoskeletal tissues Advanced manufacturing Biomaterials Tissue regeneration

小鼠排卵前后卵巢纤蛋白溶酶原激活因子活性的变化

维普期刊数据库评论

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生理学报 1989年第3期41卷 284-290页

作者：刘以训冯强柳建昌胡召元中国科学院动物研究所生殖生物学开放研究实验室

给幼龄小鼠注射PMSG刺激滤泡生长,随后注射hCG以诱发排卵。在激素处理的不同时间取出卵巢,制备卵巢匀浆液或从卵巢中分离颗粒细胞和卵丘-卵母细胞复合体,并做离体培养。样品中组织型(tPA)和尿激酶型(uPA)纤蛋白溶酶原激活因子经SDS-凝... 详细信息

给幼龄小鼠注射PMSG刺激滤泡生长,随后注射hCG以诱发排卵。在激素处理的不同时间取出卵巢,制备卵巢匀浆液或从卵巢中分离颗粒细胞和卵丘-卵母细胞复合体,并做离体培养。样品中组织型(tPA)和尿激酶型(uPA)纤蛋白溶酶原激活因子经SDS-凝胶电泳分离,用纤蛋白铺盖技术测定。实验结果表明,注射hCG 8h后15％的受试动物排卵,而卵巢匀浆液和颗粒细胞中tPA和uPA活性分别也在hCG注射后4和8h达到高峰。排卵后酶活性下降。卵丘-卵母细胞复合体主要含tPA,注射hCG 12—24h达到高峰。上述资料证明,tPA和uPA都参入小鼠排卵过程。因为排出的卵子中仍含有大量tPA,卵细胞的tPA除参与排卵外,可能对排卵后的一些生理过程也起重要作用。

关键词：纤蛋白溶酶原激活因子排卵

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改进的K-奇异值分解图像去噪算法

计量学报 2018年第3期39卷 332-336页

作者：程一峰刘增力昆明理工大学信息工程与自动化学院云南昆明650500

针对传统的K-奇异值分解信号利用率不足,采用了稀疏贝叶斯学习预处理图像信号;将正交匹配追踪与改进之后的最速下降理论相结合;因噪声原子存在于字典更新之后得到的字典中,所以结合Bartlett检验法将噪声原子裁剪掉。实验结果表明,此方... 详细信息

针对传统的K-奇异值分解信号利用率不足,采用了稀疏贝叶斯学习预处理图像信号;将正交匹配追踪与改进之后的最速下降理论相结合;因噪声原子存在于字典更新之后得到的字典中,所以结合Bartlett检验法将噪声原子裁剪掉。实验结果表明,此方法相对于小波阈值去噪法、基于离散余弦变换字典稀疏表示等去噪方法能够更好地滤除噪声,保留图像边缘信息,获得更高的峰值信噪比,得到图像视觉效果更佳。

关键词：计量学图像去噪稀疏贝叶斯学习正交匹配追踪 K-奇异值分解 K-均值聚类

蛋白激酶Cα对人正常肝和肝癌细胞中Ha-ras基因表达的影响

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生物化学与生物物理进展 2002年第5期29卷 781-785页

作者：冯怡柳惠图高萍北京师范大学生命科学学院细胞增殖及调控生物学教育部重点实验室北京100875

运用基因转染技术 ,将蛋白激酶C(PKCα)cDNA正向插入的真核表达重组质粒pXJ4 1 PKCα ,导入人正常肝细胞 (L 0 2 ) ,经蛋白质免疫印迹等检验 ,表明成功构建了稳定过表达PKCα的人正常肝细胞模型 (LT3) ,用LT3和表达反义PKCα的人肝癌细... 详细信息

运用基因转染技术 ,将蛋白激酶C(PKCα)cDNA正向插入的真核表达重组质粒pXJ4 1 PKCα ,导入人正常肝细胞 (L 0 2 ) ,经蛋白质免疫印迹等检验 ,表明成功构建了稳定过表达PKCα的人正常肝细胞模型 (LT3) ,用LT3和表达反义PKCα的人肝癌细胞HT6为细胞模型 ,通过RT PCR ,蛋白质印迹 (Westernblot)等分析和进一步运用自行构建的真核表达质粒prasGL3,进行荧光素酶活性检测表明 :过表达PKCα可以促进L 0 2细胞的增殖速率 ,并引起Ha ras基因转录水平上升和Ha ras启动子活性升高 ;反之 ,表达反义PKCα的BEL 74 0 2细胞增殖被抑制 ,Ha ras基因转录水平下降 ,Ha ras启动子活性降低 .通过实验我们首次观察到 ,PKCα亚类对Ha ras癌基因表达的影响与其对Ha ras启动子活性的作用有关 ,PKCα可能参与了对Ha

关键词：蛋白激酶Cα 人正常肝肝癌细胞 Ha-ras 基因表达

Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo feng Chongbo liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian Shao Xunming Ji Jia liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

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