检索结果-南通市图书馆

Five quinolizidine alkaloids with anti-tobacco mosaic virus activities from two species of Sophora

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第6期35卷 380-384页

作者： Ji Zhang Tong Zhang Qiao An Peng Zhang Cai-Yan Tian Chun-mao yuan Ping Yi Zhan-Xing Hu Xiao-Jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Natural Products Research Center of Guizhou Province Guiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesKunming 650201China

Three novel matrine-type alkaloids(1-3)and two unprecedented aloperine-type alkaloids(4 and 5)were isolated from the root of Sophora tonkinensis and the seeds of Sophora alopecuroides ***,compound 1 possessed an unprecedented 6/5/6 tricyclic skeleton,while compounds 2 and 3 characterized by rare 6/6/5/6 tetracyclic system and 6/6/6/6/6 pentacyclic system ***,compound 4 possessed an unprecedented 6/7/6/6 tetracyclic core,and compound 5 characterized by rare 6/6/6/6tetracyclic *** structures were elucidated by comprehensive spectroscopic data analysis and electronic circular dichroism(ECD)*** tests indicated that compound 5 displayed significant anti-tobacco mosaic virus(TMV)activity compared with the positive control ningnanmycin.

关键词： Matrine-type alkaloids Aloperine-type alkaloids Sophora tonkinensis Sophora alopecuroides Anti-tobacco mosaic virus

Uridine diphosphate glucuronosyltransferase 1A1 prevents the progression of liver injury

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第9期30卷 1189-1212页

作者： Jin-Lian Jiang Yi-Yang Zhou Wei-Wei Zhong Lin-Yan Luo Si-Ying Liu Xiao-Yu Xie mao-yuan Mu Zhi-Gang Jiang yuan Xue Jian Zhang Yi-Huai He Department of Infectious Diseases Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Infectious Diseases Jingmen Central HospitalJingmen 448000Hubei ProvinceChina Department of Respiratory Medicine Anshun People’s HospitalAnshun 561099Guizhou ProvinceChina Department of General Practice Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Intervention Radiology Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina School of Public Health Zunyi Medical UniversityZunyi 563099Guizhou ProvinceChina Department of Liver Diseases Third People’s Hospital of ChangzhouChangzhou 213000Jiangsu ProvinceChina Department of Digestion Dafang County People’s HospitalBijie 551600Guizhou ProvinceChina

BACKGROUND Uridine diphosphate glucuronosyltransferase 1A1(UGT1A1)plays a crucial role in metabolizing and detoxifying endogenous and exogenous ***,its contribution to the progression of liver damage remains *** To determine the role and mechanism of UGT1A1 in liver damage *** We investigated the relationship between UGT1A1 expression and liver injury through clinical ***,the impact and mechanism of UGT1A1 on the progression of liver injury was analyzed through a mouse model *** Patients with UGT1A1 gene mutations showed varying degrees of liver damage,while patients with acute-onchronic liver failure(ACLF)exhibited relatively reduced levels of UGT1A1 protein in the liver as compared to patients with chronic *** suggests that low UGT1A1 levels may be associated with the progression of liver *** mouse models of liver injury induced by carbon tetrachloride(CCl_(4))and concanavalin A(ConA),the hepatic levels of UGT1A1 protein were found to be *** mice with lipopolysaccharide or liver steatosis-mediated liver-injury progression,the hepatic protein levels of UGT1A1 were decreased,which is consistent with the observations in patients with ***1A1 knockout exacerbated CCl_(4)-and ConA-induced liver injury,hepatocyte apoptosis and necroptosis in mice,intensified hepatocyte endoplasmic reticulum(ER)stress and oxidative stress,and disrupted lipid *** UGT1A1 is upregulated as a compensatory response during liver injury,and interference with this upregulation process may worsen liver ***1A1 reduces ER stress,oxidative stress,and lipid metabolism disorder,thereby mitigating hepatocyte apoptosis and necroptosis.

关键词： Uridine diphosphate glucuronosyltransferase 1A1 Liver injury progression Endoplasmic reticulum stress Oxidative stress Lipid metabolism disorders

The Velocity Aberration Effect of the CSST Main Survey Camera

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第9期24卷 119-127页

作者： Hui-Mei Feng Zi-Huang Cao Man ILam Ran Li Hao Tian Xin Zhang Peng Wei Xin-Feng Li Wei Wang Hugh RAJones mao-yuan Liu Chao Liu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China University of Chinese Academy of Sciences Beijing 100049China Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK

In this study,we conducted simulations to find the geometric aberrations expected for images taken by the Main Survey Camera of the Chinese Space Station Telescope(CSST)due to its *** anticipated by previous work,our findings indicate that the geometric distortion of light impacts the focal plane's apparent scale,with a more pronounced influence as the size of the focal plane *** models suggest that the effect consistently influences the pixel scale in both the vertical and parallel *** apparent scale variation follows a sinusoidal distribution throughout one orbital *** reveal that the effect is particularly pronounced in the center of the Galaxy and gradually diminishes along the direction of ecliptic *** low ecliptic latitudes,the total aberration leads to about a 0.94 pixel offset(a 20 minute exposure)and a 0.26 pixel offset(a 300 s exposure)at the edge of the field of *** processings for the geometric effect during the CSST pre-and post-observation phases are presented.

关键词： astrometry telescopes Astronomical Instrumentation Methods and Techniques

Gamma/Hadron Separation Method for the HADAR Experiment

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren Tian-Lu Chen You-Liang Feng Dan-Zeng Luo-Bu Yi-Qing Guo Cheng Liu Qi Gao mao-yuan Liu Xiang-Li Qian Ya-Ping Wang Zi-Hao Zhang Xin-Long Li Qing-yuan Hou Heng-Jiao Liu Qing-Qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis

All-sky Guide Star Catalog for CSST

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng Zi-Huang Cao Man I Lam Ran Li Hao Tian Da-Yi Yin yuan-Yu Yang Xin Zhang Dong-Wei Fan Yi-Qiao Dong Xin-Feng Li Wei Wang Long Li Hugh RAJones Yi-Han Tao Jia-Lu Nie Pei-Pei Wang mao-yuan Liu He-jun Yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and Engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK Beijing University of Technology Beijing 100124China

The China Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan Cheng Hao Cai Shi Chen Tian-Lu Chen Xiang Dong You-Liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang Hai-Jin Li Chen Liu mao-yuan Liu Wei Liu Fang-Sheng Min Chu-Cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang Xu Wang Zhen Wang Guang-Guang Xin Yu-Hua Yao Qiang yuan Yi Zhang School of Physics and Technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research Institute Suzhou 215123China College of Physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,China,combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.22°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing Li Xin-Hua Ma Shu-Wang Cui Hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu Liu mao-yuan Liu Ye Liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin Li-Qiao Yin Heng-Yu Zhang Liang-Wei Zhang College of Physics Hebei Normal UniversityShijiazhuang 050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China Key Laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China Institute for Nuclear Research of the Russian Academy of Sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow Institute of Physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欧美新污染物监测进展及启示

中国环境监测 2024年第2期40卷 1-7页

作者：王超邢冠华薛荔栋吴静袁懋中国环境监测总站国家环境保护环境监测质量控制重点实验室北京100012

新污染物监测是新污染物环境和健康风险评估及管控的重要基础。欧美发达国家环保部门在20世纪70年代就开展了新污染物监测工作,并且2000年后形成了相应的监测制度,而我国新污染物监测工作正处于业务化起步阶段。通过深入调研欧美国家水... 详细信息

新污染物监测是新污染物环境和健康风险评估及管控的重要基础。欧美发达国家环保部门在20世纪70年代就开展了新污染物监测工作,并且2000年后形成了相应的监测制度,而我国新污染物监测工作正处于业务化起步阶段。通过深入调研欧美国家水中新污染物监测为主的发展历程、监测清单、监测要求等内容,总结出3个特点:建立动态更新的新污染物清单监测机制;将规范的新污染物监测方法作为开展监测的重要前提;充分考虑监测可行性和经济成本。结合我国现阶段新污染物监管需求及监测现状,提出我国新污染物监测工作的3点建议:明晰国家、地方新污染物监测的职责分工,建立优先监测新污染物清单动态更新机制;加强新污染物监测能力建设,建立新污染物监测标准体系;循序渐进开展新污染物监测,注重监测的可行性和可持续性。

关键词：新污染物监测清单分析方法水体欧洲美国

基于自编码器的医疗器械设备异常状态预警方法

在线全文

学校读者我要写书评

暂无评论

北京生物医学工程 2024年第4期43卷 391-397页

作者：毛媛秦琴三六三医院消毒供应中心成都610041

目的为了实时监测医疗器械设备异常状态,以便及时预警和应对设备异常情况,确保医疗器械的安全运行,提出基于自编码器的医疗器械设备异常状态预警方法。方法以某医院2022年8月起因故障停用的10台心电图监护仪为研究对象,使用数据恢复... 详细信息

目的为了实时监测医疗器械设备异常状态,以便及时预警和应对设备异常情况,确保医疗器械的安全运行,提出基于自编码器的医疗器械设备异常状态预警方法。方法以某医院2022年8月起因故障停用的10台心电图监护仪为研究对象,使用数据恢复设备连接到心电图监护仪的内部存储器,恢复和提取器械因故停用点的前1 min的全部特征数据,具体包括:信号质量和设备状态。利用多元状态估计技术构建医疗器械设备健康状态评估模型,通过对比各参数的贡献率,确定引发设备异常的关键参数。基于这些关键参数构建自编码器预警模型,将异常状态参数输入模型进行归一化处理,并计算参数误差平均值与基准值的偏差。当误差平均值偏离基准值超过60%时,触发预警机制。结果经过实验,该方法可以在3 s内准确检测出198个异常样本,证实了该预警方法能够在短时间内准确检测出异常样本。同时,为进一步分析该医疗器械设备的具体故障原因,运用3种方法分别对设备各个故障原因进行识别与定位,以贡献率为衡量标准,并与实际贡献率进行对比分析,该方法贡献率与实际贡献率数值较为接近,可以全面预测引起医疗器械设备异常情况。结论基于自编码器的医疗器械设备异常状态的预警方法具有高度的精确性和先导性,为实时监测和预警医疗器械设备异常状态提供了有效的技术手段,有助于提升医疗器械的安全性和可靠性。

关键词：医疗器械设备多元状态估计贡献率分析自编码器异常状态预警

维普期刊数据库博看期刊