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赶黄草化学成分及药理活性研究进展

辽宁大学学报（自然科学版） 2024年第2期51卷 121-129页

作者：吕晶田新强项峥陈长兰辽宁大学药学院辽宁沈阳110036

赶黄草(Penthorum chinense Pursh)为传统苗族药物,是一种民间用于预防治疗肝病的“药食同源”植物,性温味甘,具有清热解毒、利水消肿、平肝等功效.现代天然药物化学研究表明,赶黄草含有丰富的活性成分,包括黄酮类、木脂素类、有机酸类... 详细信息

赶黄草(Penthorum chinense Pursh)为传统苗族药物,是一种民间用于预防治疗肝病的“药食同源”植物,性温味甘,具有清热解毒、利水消肿、平肝等功效.现代天然药物化学研究表明,赶黄草含有丰富的活性成分,包括黄酮类、木脂素类、有机酸类、香豆素类等化学成分,具有抗肿瘤、抗氧化、抗炎和肝损伤的保护作用等多种药理活性,药食用价值较高.近年来,虽然赶黄草的化学成分及其药理作用研究逐渐深入,然而相关综述较少.本文对国内外研究成果进行了综述,以期为赶黄草的药理作用机制研究及“药食同源”新型保健产品的开发提供参考.

关键词：赶黄草化学成分药理活性药食同源

Anti-noise performance of the pulse coupled neural network applied in discrimination of neutron and gamma-ray

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Nuclear Science and Techniques 2022年第6期33卷 89-101页

作者： Hao-Ran Liu Zhuo Zuo Peng Li Bing-Qi Liu lan chang Yu-Cheng Yan State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China The Engineering and Technical College of Chengdu University of Technology Leshan 614000China Southwestern Institute of Physics Chengdu 610225China Chengdu University Chengdu 610106China

In this study,the anti-noise performance of a pulse-coupled neural network(PCNN)was investigated in the neutron and gamma-ray(n-γ)discrimination *** experiments were conducted in two *** the first group,radiation pulse signals were pre-processed using a Fourier filter to reduce the original noise in the signals,whereas in the second group,the original noise was left untouched to simulate an extremely high-noise *** each part,artificial Gaussian noise with different intensity levels was added to the signals prior to the discrimination *** the aforementioned conditions,the performance of the PCNN was evaluated and compared with five other commonly used methods of n-γdiscrimination:(1)zero crossing,(2)charge comparison,(3)vector projection,(4)falling edge percentage slope,and(5)frequency gradient *** experimental results showed that the PCNN method significantly outperforms other methods with outstanding FoM-value at all noise ***,the fluctuations in FoM-value of PCNN were significantly better than those obtained via other methods at most noise levels and only slightly worse than those obtained via the charge comparison and zerocrossing methods under extreme noise ***,the changing patterns and fluctuations of the FoMvalue were evaluated under different noise ***,based on the results,the parameter selection strategy of the PCNN was *** conclusion,the PCNN method is suitable for use in high-noise application scenarios for n-γdiscrimination because of its stability and remarkable discrimination *** does not rely on strict parameter settings and can realize satisfactory performance over a wide parameter range.

关键词： Pulse coupled neural network Zero crossing Frequency gradient analysis Vector projection Charge comparison Neutron and gamma-ray discrimination Pulse shape discrimination

Ambient Fine Particulate Matter Exposure and Blood Pressure:Evidence from a Large Chinese Multiple Follow-Up Study

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Biomedical and Environmental Sciences 2023年第1期36卷 38-49页

作者： JIANGTULU Bahabaike lan chang Xin CHEN Jun Xi CHEN Xi WANG Bin XUE Tao Institute of Reproductive and Child Health Key Laboratory of Reproductive HealthNational Health Commission of the People's Republic of ChinaBeijing 100191China Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China National Institute of Environmental Health Chinese Center for Disease Control and Prevention(China CDC)Beijing 102206China

Objective This study aimed to investigate the association of ambient PM_(2.5)exposure with blood pressure(BP)at the population level in *** A total of 14,080 participants who had at least two valid blood pressure records were selected from the China Health and Retirement Longitudinal Survey during 2011–*** long-term PM_(2.5)exposure was assessed at the geographical level,on the basis of a regular 0.1°×0.1°grid over China.A mixed-effects regression model was used to assess *** Each decrease of 10μg/m^(3)in the 1 year-mean PM_(2.5)concentration(FPM1Y)was associated with a decrease of 1.24[95%confidence interval(CI):0.84–1.64]mmHg systolic BP(SBP)and 0.50(95%CI:0.25–0.75)mmHg diastolic BP(DBP),respectively.A robust association was observed between the long-term decrease in PM_(2.5)and decreased BP in the middle-aged and older *** a generalized additive mixed model,we further found that SBP increased nonlinearly overall with FPM1Y but in an approximately linear range when the FPM1Y concentration was<70μg/m^(3);In contrast,DBP increased approximately linearly without a clear *** Efficient control of PM_(2.5)air pollution may promote vascular health in *** study provides robust scientific support for making the related air pollution control policies.

关键词： Fine particulate matter PM_(2.5) Blood pressure Risk assessment Preventive medicine

沉默信息调节因子2在瑞芬太尼诱发的大鼠切口痛觉过敏中的作用及其机制研究

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现代生物医学进展 2024年第4期24卷 601-605,611页

作者：周瑜常兰兰朱魏刘晓杰吴迷迷孙玉娥薄靳华南京大学医学院附属鼓楼医院麻醉科江苏南京210008 济南市第七人民医院麻醉手术科山东济南250000

目的:探讨沉默信息调节因子2(Sirt2)在瑞芬太尼诱发的大鼠切口痛觉过敏中的作用及其机制。方法:18只SD大鼠采用随机数字表法分为I组(切口组,n=6),RI组(瑞芬太尼+切口组,n=6)和RI+Sirt2过表达组(瑞芬太尼+切口+Sirt2过表达组,n=6)。I组... 详细信息

目的:探讨沉默信息调节因子2(Sirt2)在瑞芬太尼诱发的大鼠切口痛觉过敏中的作用及其机制。方法:18只SD大鼠采用随机数字表法分为I组(切口组,n=6),RI组(瑞芬太尼+切口组,n=6)和RI+Sirt2过表达组(瑞芬太尼+切口+Sirt2过表达组,n=6)。I组在大鼠足底制作切口痛模型的同时在腹部注射等容量生理盐水30 min,RI组和RI+Sirt2过表达组在足底进行切口痛模型制作的同时并泵注瑞芬太尼30 min,RI+Sirt2过表达组在脊髓水平提前1周注射Sirt2过表达慢病毒处理。各组大鼠分别于泵注瑞芬太尼或生理盐水术前24 h,泵注结束后2 h、6 h、24 h和48 h测定机械刺激缩足反应阈值(MWT)及热缩足潜伏期(TWL)。行为学测试结束后处死大鼠,取L3-5脊髓节段,采用蛋白免疫印迹(Western blot)法检测Sirt2表达,超氧化物歧化酶2(SOD2)活性采用酶联免疫吸附法(ELISA)法测定,超氧阴离子水平和NADPH氧化酶活性采用化学发光法测定。结果:各组大鼠MWT和TWL的时间效应(F=683.602,624.033,均P<0.001)和组别×时间交互效应显著(F=9.142,4.550,均P<0.001),说明MWT和TWL有随时间变化的趋势并且时间因素的作用有随组别的不同而不同,组间比较差异有统计学意义(F=93.157,25.176,均P<0.001)。与I组比较,RI组T_(1-4)时MWT降低,TWL缩短(P<0.05);RI+Sirt2过表达组T2、T4时间点MWT降低,T_(2-4)时间点TWL缩短(P<0.05)。与RI组比较,RI+Sirt2过表达组T_(3-4)时间点MWT升高,T_(2-4)时间点TWL延长(P<0.05)。三组大鼠Sirt2蛋白表达比较差异有统计学意义(F=265.643,P<0.001);与I组比较,RI组和RI+Sirt2过表达组术后48 h脊髓组织Sirt2表达水平减少(P<0.05);与RI组比较,RI+Sirt2过表达组术后48 h脊髓组织Sirt2表达水平增加(P<0.05)。三组大鼠脊髓组织SOD2活性、NADPH氧化酶活性、超氧化物阴离子表达比较差异有统计学意义(F=13.543,14.813,19.675,均P<0.001);与I组比较,RI组和RI+Sirt2过表达组术后48 h脊髓组织SOD2活性水平降低,NADPH氧化酶活性和超氧化物阴离子水平增加(P<0.05);与RI组比较,RI+Sirt2过表达组术后48 h脊髓组织SOD2活性水平增加,NADPH氧化酶活性和超氧化物阴离子减低(P<0.05)。结论:Sirt2通过调节氧化应激水平参与瑞芬太尼诱发切口痛大鼠痛觉过敏过程。

关键词：沉默信息调节因子2 瑞芬太尼大鼠痛觉过敏氧化应激

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai Xue lan Xie chang-Mei Wu Qiang Zheng Department of Polymer Materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Improved Cohen-Sutherland algorithm for TGS transmission imaging

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Nuclear Science and Techniques 2023年第6期34卷 91-102页

作者： Yu-Cheng Yan Ming-Zhe Liu Xing-Yu Li Yu-Ting Xiong Yao Tan Zhuo Zuo lan chang Cui Li State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China The Engineering and Technical College of Chengdu University of Technology Leshan614000China Southwestern Institute of Physics Chengdu610225China Sichuan University of Science and Engineering Zigong643000China

Tomographic gamma scanner(TGS),an advancedγ-ray nondestructive analysis technique,can locate and analyze nuclides in radioactive nuclear waste,and TGS can be categorized into two processes:e.g.,transmission measurement and emission ***,transmission measurements provide the basis for accurate measurement of nonuniform radionuclide content in TGS *** scan data were obtained using the Monte Carlo tool Geant4 simulation,and 25 voxels were divided into five lengths and five widths in a square *** this study,an encoding cropping algorithm based on draped foot vector judgment was adopted to rapidly calculate the voxel trace matrix within a square bucket of nuclear waste,and the transmission images were reconstructed using ordered subset expectation *** results indicated that the cropping speed of the improved coding algorithm was significantly higher than that of the original algorithm,and the relative mean deviation and root-mean-square error between the reconstructed attenuation coefficient and the reference standard value tended to decrease with an increase in the cropped line segments in the voxel;the Pearson correlation coefficient tended to converge to *** image quality evaluation parameters of the high media-density materials were better than those of the low media-density materials in the above three *** reconstruction effect was relatively poor for more complex filling *** there were more than 10 cropped line segments in the voxel,the reconstruction data generally tended to be *** graphical trimming algorithm can rapidly calculate the trace matrix of the scanned voxels;it exhibits the advantages of speed and efficiency and can serve as a novel method to solve the trace matrix of TGS nuclear waste transmission scans.

关键词： TGS Cohen-Sutherland Transmission scanning Trace matrix

室内复杂条件下高凌空吊挂楼层后安装施工技术

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建筑技术 2024年第12期55卷 1508-1511页

作者：高伟李雅男张岩黄丽颖兰海昌北京建工集团有限责任公司北京100055 北京建工集团(雄安)建设有限公司河北雄安071000

室内吊挂楼层呈现分布区域多、凌空高度高、形式多样、杆件繁多、结构整体刚度小,施工均需在主体结构施工完成后安装的特点。如何解决高凌空吊挂楼层在室内复杂条件下无法使用常规机械安装的难题有其重要意义。通过研发室内复杂条件下... 详细信息

室内吊挂楼层呈现分布区域多、凌空高度高、形式多样、杆件繁多、结构整体刚度小,施工均需在主体结构施工完成后安装的特点。如何解决高凌空吊挂楼层在室内复杂条件下无法使用常规机械安装的难题有其重要意义。通过研发室内复杂条件下高凌空吊挂楼层后安装施工技术,解决了其室内复杂条件下高凌空吊挂楼层后安装的难题。该技术通过在地面整体拼装吊挂结构,在吊挂安装楼层上部设置提升支撑架,有效解决了现有技术中吊挂楼层安装存在的安全隐患问题,同时相比常规的吊挂楼层安装施工技术有更好的经济效益与社会效益。

关键词：室内复杂条件下后安装吊挂楼层

Microstructure Evolution and Nanomechanical Behavior of Micro-Area in Molten Pool of Selective Laser Melting(CoCrNi)_(82)Al_(9)Ti_(9)High-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1019-1033页

作者： Hong-Wei Zhang Li-Wei lan Zhe-Yu Yang chang-Chun Li Wen-Xian Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Ministry of Education Key Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyTaiyuan030024China Shanxi-Zhejiang University New Materials and Chemical Research Institute Taiyuan030032China

In this work,the phase evolution mechanism and nanomechanical properties of(CoCrNi))(82)Al_(9)Ti_(9)high-entropy alloy(HEA)prepared by selective laser melting(SLM)in the molten pool were *** HEA contains multiple primary elements and undergoes high-temperature gradient and rapid cooling during *** leads to significant inhomogeneity of nano-scale microstructure characteristics and instability of *** optimizing process parameters,the microstructure evolution at the optimal parameter volume energy density of 440 J/mm^(3)was studied.A phase transition from BCC to FCC occurred in the melt *** the micro-area of the melt pool results in a temperature rise and the combustion-induced loss of Al ***,the Ni element content increases significantly outside the melt *** process enhances the phase stability of FCC and facilitates phase ***,rapid cooling leads to the formation of distinctive ultrafine equiaxial crystals inside the melt pool,accompanied by the generation of intracrystalline needle-like nano-scale *** the melt pool,the accumulation of energy results in the formation of coarse ***,the nano-hardness inside the molten pool is remarkably high at 11.79 GPa,while the outside the molten pool is reduced to 9.58 *** the fracture toughness outside the melt pool also *** with inside the melt pool,the residual stress outside the melt pool changed from compressive to tensile stress and decreased from 603.28 to 322.84 MPa.

关键词： High-entropy alloys Selective laser melting Microstructure evolution Nanoindentation

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2024年第3期19卷 619-628页

作者： Jun chang Yujiao Li Xiaoqian Shan Xi Chen Xuhe Yan Jianwei Liu lan Zhao First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina Tianjin University of Traditional Chinese Medicine TianjinChina

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s ***,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be *** to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to *** events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian ***,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative *** this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

关键词： Alzheimer’s disease amyloid-β cell therapy extracellular vesicle neural stem cell synaptic plasticity tau