检索结果-南通市图书馆

Effects of displacement current on wave dispersion relation and polarization properties in auroral plasmas

Research in Astronomy and Astrophysics 2021年第10期21卷 108-118页

作者： Liang Xiang Bing Ma Qiu-Huan Li Ling Chen hong-wei yu De-Jin Wu Institute of Space Physics Luoyang Nonnal UniversityLuoyang 471934China Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China University of Science and Technology of China Hefei 230026China

In-situ observations from the FREJA magnetospheric research satellite and the Fast Auroral SnapshoT satellite have shown that plasma waves are frequently observed in the auroral plasma,which are believed to be fundamentally important in wave energy dissipation and particle ***,the effects of a displacement current on these waves have not been *** on the two-fluid theory,we investigate the dispersion relation and polarization properties of fast,Alfven,and slow modes in the presence of a displacement current,and the effects of the displacement current on these waves are also *** results show that the wave frequency,polarization,magnetic helicity and other properties for the fast and Alfven modes are highly sensitive to the normalized Alfven velocity v_(A)/c,plasma beta β,and propagation angle θ,while for the slow mode the dependence is *** particular,for both fast and Alfven modes,the magnetic helicity is obviously different with and without the displacement current,especially for the Alfven mode with the helicity reversals from right-handed to left-handed when v_(A)/c increases from 0 to *** charge-neutral condition of both fast and Alfven modes with frequencies larger than the proton cyclotron frequency is invalid in the presence of the displacement ***,the presence of the displacement current leads to relatively large magnetic compressibility for the Alfven mode and relatively large electron compressibility for the fast *** results can be useful for a comprehensive understanding of the wave properties and the physics of particle energization phenomena in auroral plasmas.

关键词： waves magnetohydrodynamics(MHD) planets and satellites:aurorae

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Congeneric invasive versus native plants utilize similar inorganic nitrogen forms but have disparate use efficiencies

引用

Journal of Plant Ecology 2021年第2期14卷 180-190页

作者： hong-wei yu wei-Ming He State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Aims Soil inorganic nitrogen(N)has long been recognized to play an important role in plant *** comparing the N use strategies of multiple invasive versus native plant congeners along an entire N gradient is key to understanding plant invasion success,there are few related *** We conducted a potted experiment with six invasive and native congeneric pairs,which were subjected to 11 nitrate/ammonium(NO3−/NH4+)ratios(i.e.100%NO3−at one end and 100%NH4+at the other end),each with low-and high-N *** species–N combination was replicated eight times,and thus there were 2112 pots in *** measured the following traits:the total biomass,growth advantage,biomass allocation,leaf chlorophyll content and low-N *** Findings Invasive and native congeners grew well at any NO3−/NH4+ratios,and their responses of growth,allocation and tolerance were approximately parallel along the 11 NO3−/NH4+ratios across two N *** invaders grew larger and had greater chlorophyll contents,higher root biomass allocation and stronger low-N tolerance than their congeneric *** findings suggest that invasive and native plant congeners may utilize similar inorganic N forms(***3−and NH4+)across an entire N composition gradient and that higher N use efficiencies could favor alien plants to invade new plant communities where congeneric natives are dominants.

关键词： biomass allocation chlorophyll content low-N tolerance N use efficiency plant invasiveness

来源：

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

A case of paracentral acute middle maculopathy after small incision lenticule extraction surgery

引用

International Journal of Ophthalmology(English edition) 2022年第1期15卷 169-171页

作者： Li-Hui Meng Xin-yu Zhao wei-hong yu You-Xin Chen Department of Ophthalmology Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Key Laboratory of Ocular Fundus Diseases Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Dear Editor,Paracentral acute middle maculopathy(PAMM)is characterized by optical coherence tomography(OCT)finding of a hyper-reflective band spanning the inner nuclear layer(INL),which is primarily due to ischemic hy... 详细信息

关键词： capillary spanning finding

来源：

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

‘‘Amano'' lipase DF-catalyzed efficient synthesis of 2,20-arylmethylene dicyclohexane-1,3-dione derivatives in anhydrous media

引用

Chinese Chemical Letters 2014年第8期25卷 1190-1192页

作者： Ling Jiang Bo Wang Rong-Rong Li Sa Shen hong-wei yu Li-Dan Ye Department of Chemical and Biological Engineering Zhejiang University College of Materials and Chemical Engineering Hainan University School of Chemical and Material Engineering Jiangnan University

A simple and efficient method was developed for the synthesis of 2.2＇-arylmethylene dicyclohexane-1,3- dione derivatives via the Knoevenagel-Michael cascade reactions of aromatic aldehydes and 1,3-cyclic diketones catalyzed by ＂Amano＂ lipase DF, which expands the application field of enzyme catalytic promiscuity. This protocol provides several advantages over the traditional chemical synthesis, such as simple work-up procedure, high yields Cup to 94%） and environmental friendliness.

关键词： "Amano" lipase DF Knoevenagel condensation Michael addition Catalytic promiscuity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of polymer-supported phosphine from ferrocene for palladium-catalyzed Suzuki-Miyaura cross-coupling reactions

引用

Chinese Chemical Letters 2007年第1期18卷 37-40页

作者： hong wei yu Qing Song Tong Yi Ru Peng Li Jia Ji Cheng Shi Zi Lin Jin State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China College of Chemistry and Materials Science Fujian Provincial Key Laboratory of Polymer Materials Fujian Normal University Fuzhou 350007 China

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki- Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain correspond... 详细信息

关键词： Immobilization Palladium Suzulki-Miyaura reaction Biaryl Catalysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A new digital pulse processing method for 2πa and 2πb emitter measurement

引用

Nuclear Science and Techniques 2016年第6期27卷 137-143页

作者： Zheng Tu Ke-Zhu Song Ming Zhang Zhi-Jie Yang Zhi-Guo Ding hong-wei yu Jun-Cheng Liang Hao-Ran Liu State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China National Institute of Metrology 18 North Third Ring EastRd.Beijing 100029China

Digital pulse processing has developed rapidly during recent ***,it has been widely applied in many *** this study,we introduce a digital pulse processing method for 2πa and 2πb emitter *** digital pulse processing method for 2πa and 2πb emitter measurement is comprised of a field-programmable gate-array-based acquisition card and a pulse-height analysis *** established two channels(one for the a emitter and one for the b emitter) on an acquisition board using an analog-to-digital converter with a 16-bit resolution at a speed of 100 million samples per *** this study,we used captured and stored data to analyze emission rate counts and *** method we established takes into account noise cancelation,dead-time correction,background subtraction,and zero-energy *** carefully designed control procedures in order to simplify pulse-width fitting and threshold-level *** transmitted data and commands through a universal serial bus between the acquisition board and the *** results of our tests prove that our method performs well in pulse reconstruction fidelity and amplitude measurement *** with the current standard method for measuring 2πa and 2πb emission rates,our system demonstrates excellent precision in emission rate counting.

关键词：脉冲处理测量性能发射器顺序控制程序 π 数据采集卡测量精度模数转换器

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Immunohistochemical　study　of　gastrin　in　colorectal　carcinoma　tissues　and　its　adjacent　mucosa

引用

World Journal of Gastroenterology 1997年第2期3卷 27-29页

作者： JIANG Chun Ping, CHEN yu Quan, ZHU Jian wei, SHEN hong Xun and yu Xiu

AIM To study the expression of gastrin in colorectal carcinoma tissues and its adjacent mucosa and discuss the action of gastrin on colorectal carcinoma. METHODS The gastrin expression in colorectal carcinoma tissues and its adjacent mucosa of 58 cases was examined by using immunohistochemical and immunoelectron microscopic technique. RESULTS Of the transitional mucosa (TM) of co_ lorectal carcinoma, nontypical dysplasia mucosa and carcinoma tissue, the positive rate of gastrin is 35 1%, 48 3% and 60 3% respectively, with an increasing trend ( P <0 05). The granules of protein A gold (PAG) of immunoelectron microscopy may be seen in different electro density secreting granules in carcinoma cells and intercellular spaces or on the surface of membrane microvillus. CONCLUSION The existence of gastrin in colorectal carcinoma tissue and its adjacent mucosa, and the carcinoma cells forming gastrin granules to release the gastrin may be one of the initial factors in occurrence and development of the carcinoma. Positive expression of gastrin in colorectal carcinoma tissues serves as a marker indicating a good differentiation.

关键词： colorectal neoplasms gastrin immunohistochemistry microscopy, electron

来源：

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

Chinese Guideline on the Management of Polypoidal Choroidal Vasculopathy (2022)

引用

Chinese Medical Sciences Journal 2023年第2期38卷 77-93页

作者： You-Xin Chen yu-Qing Zhang Chang-Zheng Chen hong Dai Su-Yan Xiang Ma Xiao-Dong Sun Shi-Bo Tang yu-Sheng Wang Wen-Bin wei Feng Wen Ge-Zhi Xu wei-hong yu Mei-Xia Zhang Ming-wei Zhao Yang Zhang Fang Qi Xun Xu Xiao-Xin Li Department of Ophthalmology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing China Key Laboratory of Ocular Fundus Diseases Chinese Academy of Medical Sciences&Peking Union Medical College Department of Health Research Methods Evidenceand ImpactMc Master University Ningbo Nottingham GRADE center University of Nottingham Institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences CEBIM(Center for Evidence Based Integrative Medicine)-Clarity Collaboration Guang'anmen HospitalChina Academy of Chinese Medical Sciences Department of Ophthalmology Renmin Hospital of Wuhan University Department of Ophthalmology Beijing Hospital Department of Ophthalmology Xuzhou Municipal Hospital Affiliated to Xuzhou medical University Department of Ophthalmology the First Affiliated Hospital of Dalian Medical University Department of Oph thalmology Shanghai General HospitalShanghai Jiao Tong University School of Medicine Aire Eye Hospital Department of Ophthalmology Xijing HospitalFouth Military Medical University Department of Ophthalmology Beijing Tongren Hospital State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University Ophthalmology the Affiliated Eye and ENT HospitalShanghai Medical SchoolFudan University Department of Ophthalmology West China School of MedicineWest China HospitalSichuan University Department of Ophthalmology Peking University People’s Hospital Systematic Review Solutions Ltd Department of Ophthalmology Shanghai General Hospital Eye Center of Xiamen University People Eye Center of People’s Hospital Peking University

Background In China's Mainland,patients with neovascular age-related macular degeneration(nAMD)have approximately an 40%prevalence of polypoidal choroidal vasculopathy(PCV).This disease leads to recurrent retinal pigment epithelium detachment(PED),extensive subretinal or vitreous hemorrhages,and severe vision *** has introduced various treatment modalities in the past years and gained comprehensive experience in treating *** A total of 14 retinal specialists nationwide with expertise in PCV were empaneled to prioritize six questions and address their corresponding outcomes,regarding opinions on inactive PCV,choices of anti-vascular endothelial growth factor(anti-VEGF)monotherapy,photodynamic therapy(PDT)monotherapy or combined therapy,patients with persistent subretinal fluid(SRF)or intraretinal fluid(IRF)after loading dose anti-VEGF,and patients with massive subretinal *** evidence synthesis team conducted systematic reviews,which informed the recommendations that address these *** guideline used the GRADE(Grading of Recommendations,Assessment,Development,and Evaluation)approach to assess the certainty of evidence and grade the strengths of *** The panel proposed the following six conditional recommendations regarding treatment choices.(1)For patients with inactive PCV,we suggest observation over treatment.(2)For treatment-na?ve PCV patients,we suggest either anti-VEGF monotherapy or combined anti-VEGF and PDT rather than PDT monotherapy.(3)For patients with PCV who plan to initiate combined anti-VEGF and PDT treatment,we suggest later/rescue PDT over initiate PDT.(4)For PCV patients who plan to initiate anti-VEGF monotherapy,we suggest the treat and extend(TE)regimen rather than the pro re nata(PRN)regimen following three monthly loading doses.(5)For patients with persistent SRF or IRF on optical coherence tomography(OCT)after three monthly anti-VEGF treatments,we suggest proceeding with anti-VEGF treatment r

关键词： polypoidal choroidal vasculopathy anti-vascular endothelial growth factor photodynamic therapy surgery

来源：

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

DNA Methylation and Uveal Melanoma

引用

Chinese Medical Journal 2018年第7期131卷 845-851页

作者： Zhi-Kun Yang Jing-yun Yang Zhuo-Zai Xu wei-hong yu Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Rush Alzheimer's Disease Center Rush University Medical Center Chicago IL 60612 USA Department of Neurological Sciences Rush University Medical Center Chicago IL 60612 USA Department of Ophthalmology Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China

Objective： The objective of the study was to summarize the role of DNA methylation in the development and metastasis of uveal melanoma （UM）. Data Sources： The relevant studies in MEDLINE were searched. Study Selection： In this review, we performed a comprehensive literature search in MEDLINE using ＂uveal melanoma＂ AND （＂DNA methylation＂ OR ＂epigenetics＂） for original research/review articles published before February 2018 on the relationship between DNA methylation and UM. References of the retrieved studies were also examined to search for potentially relevant papers. Results： Previous studies on the relationship between DNA methylation and UM covered many genes including tumor suppressor genes （TSGs）, cyclin-dependent kinase genes, and other genes. Among them, the TSG genes such as RASSFIA and p16INK4a, which encodes a cyclin-dependent kinase inhibitor, are relatively well-studied genes. Specifically, a high percentage of promoter methylation of RASSF1A was observed in UM cell lines and/or patients with UM. Promoter methylation of RASSFIA was also associated with the development of metastasis. Similarly, a high percentage of promoter hypernlethylation of p16INK4a was found in UM cell lines. DNA promoter methylation can control the expression of p16INK4a, which affect cell growth, migration, and invasion in UM. Many other genes might also be involved in the pathogenesis of UM such as tile Ras and EF-hand domain containing （RASEF） gene, RAB31, hTERT, embryonal fyn-associated substrate, and deleted in split-hand/split-foot 1. Conclusions： Our review reveals the complex mechanisms underlying the tumorigenesis of UM and highlights the great needs of future studies to discover more genes/5＇-C-phosphate-G-3＇ sites contributing to the development/metastasis of U M and explore the mechanisms through which epigenetic changes exert their function in UM.

关键词： DNA Methylation Epigenetics Metastasis Uveal Melanoma

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Artificial intelligence can assist with diagnosing retinal vein occlusion

引用

International Journal of Ophthalmology(English edition) 2021年第12期14卷 1895-1902页

作者： Qiong Chen wei-hong yu Song Lin Bo-Shi Liu Yong Wang Qi-Jie wei Xi-Xi He FeiDing Gang Yang You-Xin Chen Xiao-Rong Li Bo-Jie Hu Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Key Lab of Ocular Fundus Diseases Chinese Academy of Medical SciencesDepartment of OphthalmologyPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100032China Vistel AI Lab Visionary Intelligence LtdBeijing 100081China School of Information Renmin University of ChinaBeijing 100081China

AIM:To assist with retinal vein occlusion(RVO)screening,artificial intelligence(AI)methods based on deep learning(DL)have been developed to alleviate the pressure experienced by ophthalmologists and discover and treat RVO as early as ***:A total of 8600 color fundus photographs(CFPs)were included for training,validation,and testing of disease recognition models and lesion segmentation *** disease recognition and four lesion segmentation models were established and ***,one disease recognition model and one lesion segmentation model were selected as ***,224 CFPs from 130 patients were included as an external test set to determine the abilities of the two selected ***:Using the Inception-v3 model for disease identification,the mean sensitivity,specificity,and F1 for the three disease types and normal CFPs were 0.93,0.99,and 0.95,respectively,and the mean area under the curve(AUC)was *** the DeepLab-v3 model for lesion segmentation,the mean sensitivity,specificity,and F1 for four lesion types(abnormally dilated and tortuous blood vessels,cotton-wool spots,flame-shaped hemorrhages,and hard exudates)were 0.74,0.97,and 0.83,***:DL models show good performance when recognizing RVO and identifying lesions using *** of the increasing number of RVO patients and increasing demand for trained ophthalmologists,DL models will be helpful for diagnosing RVO early in life and reducing vision impairment.

关键词： artificial intelligence disease recognition lesion segmentation retinal vein occlusion

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：