检索结果-南通市图书馆

Virologica Sinica 2021年第5期36卷 997-1005页

作者： Yuanchao Xie Xiaozhen Guo tianwen Hu Daibao Wei Xiuli Ma Jiaqiang Wu Bing Huang Jingshan Shen Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China Institute of Poultry Science Shandong Academy of Agricultural SciencesJinan 250023China University of Chinese Academy of Sciences Beijing 100049China

Porcine epidemic diarrhea(PED)caused by porcine epidemic diarrhea virus(PEDV)is widespread in the *** recent years,the increased virulence of the virus due to viral variations,has caused great economic losses to the pig industry in many *** is always worthy to find effective therapeutic methods for *** an important class of antivirals,nucleoside drugs which target viral polymerases have been applied in treating human viral infections for half a ***,we evaluated the anti-PEDV potential of three broad-spectrum antiviral nucleoside analogs,remdesivir(RDV),its parent nucleoside(RDV-N)andβ-D-N^(4)-hydroxycytidine(NHC).Among them,RDV-N was the most active agent in Vero E6 cells with EC_(50) of 0.31μmol/L,and more potent than RDV(EC_(50)=0.74μmol/L)and NHC(EC_(50)=1.17μmol/L).The activity of RDV-N was further confirmed using an indirect immuno-fluorescence ***,RDV-N exhibited a good safety profile in cells and in *** high sequence similarity of the polymerase functional domains of PEDV with other five porcine coronaviruses indicated a broader antiviral spectrum for the three ***,RDV-N is a promising broad-spectrum antiviral nucleoside,and it would be worthy to make some structural modifications to increse its oral bioavailability.

关键词： Porcine epidemic diarrhea virus(PEDV) Nucleoside analog RNA dependent RNA polymerase(RdRp) Antiviral activity

在线全文

学校读者我要写书评

暂无评论

酶固定化技术的最新研究进展

西安工程大学学报 2024年第1期38卷 83-91页

作者：潘虹陆天炆王晓军洪一楠西安工程大学环境与化学工程学院陕西西安710048

酶作为一种催化性能好且安全可靠的生物催化剂,在食品、医药及环境治理等诸多领域得到了广泛应用,但因受限于游离酶较差的环境稳定性而难以实现进一步的工业化应用。酶固定化技术有助于提高游离酶对敏感环境的耐受性和操作过程中的稳定... 详细信息

酶作为一种催化性能好且安全可靠的生物催化剂,在食品、医药及环境治理等诸多领域得到了广泛应用,但因受限于游离酶较差的环境稳定性而难以实现进一步的工业化应用。酶固定化技术有助于提高游离酶对敏感环境的耐受性和操作过程中的稳定性,大大缩减了应用成本。回顾了近五年内固定化技术的发展及现状,总结了吸附法、结合法等传统固定化方法,共固定化酶法等新型固定化方法,以及天然材料载体、复合材料载体和纳米载体等不同固定化载体在各个领域的研究进展。相比于游离酶,固定化酶体系在稳定性和重复使用性等方面得到了显著提升,但同时也存在一些不足,如固定后的活性回收率降低、载体合成途径繁琐且成本较高以及固定化酶作用机理尚不完善等。结合这些不足之处提出了酶固定化技术在未来的发展方向。

关键词：酶固定化固定化载体固定化方法纳米载体共固定

维普期刊数据库博看期刊

Improve the throughput of M-to-1 free-space optical systems by employing uniquely decodable codes

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2023年第3期21卷 35-40页

作者：李亚添耿天文高世杰 Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China

This paper utilizes uniquely decodable codes[UDCs]in an M-to-1 free-space optical[FSO]*** from UDCs’nonorthogonal nature,the sum throughput is *** first prove that the uniquely decodable property still holds,even in optical fading *** is further discovered that the receiver can extract each source’s data from superimposed symbols with only one processing *** to theoretical analysis and simulation results,the throughput gain is up to the normalized UDC’s sum rate in high signal-to-noise ratio *** equivalent desktop experiment is also implemented to show the feasibility of the UDC-FSO structure.

关键词： free-space optics throughput enhancement uniquely decodable code

Application of nonlinear color matching model to four-color ink-jet printing

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2002年第3期9卷 270-275页

作者： SU Xiaohong(苏小红) ZHANG tianwen(张田文) GUO Maozu(郭茂祖) WANG Yadong(王亚东) School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

Through discussing the color matching technology and its application in printing industry the conventional approaches commonly used in color matching, and the difficulties in color matching, a nonlinear color matching model based on two step learning is established by finding a linear model by learning pure color data first and then a nonlinear modification model by learning mixed color data. Nonlinear multiple regression is used to fit the parameters of the modification model. Nonlinear modification function is discovered by BACON system by learning mixture data. Experiment results indicate that nonlinear color conversion by two step learning can further improve the accuracy when it is used for straightforward conversion from RGB to CMYK. An improved separation model based on GCR concept is proposed to solve the problem of gray balance and it can be used for three to four color conversion as well. The method proposed has better learning ability and faster printing speed than other historical approaches when it is applied to four color ink jet printing.

关键词： Color-matching nonlinear multiple regression fuzzy incidence cluster four-color ink-jet printing.

Hierarchical Energy Management for Economic Operation of Micro Energy Internet Systems

在线全文

学校读者我要写书评

暂无评论

Hierarchical Energy Management for Economic Operation of Mic...

An applied research on remote sensing classification in the Loess Plateau

第36届中国控制会议

作者： Wei Liu tianwen Zheng Zhenquan Sun Laijun Chen Lifeng Li Shengwei Mei Shaanxi Regional Electric Power Group Co.Ltd. State Key Lab of Power System Department of Electrical EngineeringTsinghua University Qinghai Key Lab of Efficient Utilization of Clean Energy(New Energy Photovoltaic Industry Research Center Qinghai University)

ISBN: (纸本)9781538629185

In this paper,the concept of micro energy internet is discussed *** achieve economic and environmental goal in the operation of micro energy internet,a hierarchical energy management system is proposed to handle the power flow exchanged between the micro energy internet and the host ***,the concept,characteristics and operational goals of micro energy internet is ***,a three-layer hierarchical optimization model concerning energy efficiency and environmental issue is proposed based on the game theory.A micro energy internet consists of an electricity network and thermal network is investigated and the effectiveness of the proposed management system is validated.

关键词： Hierarchical energy management Micro energy internet Multi objective functions

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 2003年第4期13卷 395-399页

作者： LIU Yongmei TANG Guoan LI tianwen YANG Qinke Department of Urban and Resource Science Northwest University Xi'an 710069 Institute of Soil and Water Conservation CAS and Ministry of Water Resources Yangling 710069

Dae to complex terrain of the Loess Plateau, the classification accuracy is unsatisfactory when a single supervised classification is used in die remote sensing investigation of the sloping field. Taking the loess hill and gully area of northern Shaanxi Province as a test area, a research was conducted to extract sloping field and other land use categories by applying an integrated classification. Based on an integration of supervised classification aad unsupervised classification, sampling method is remarkably unproved. The results show that the classification accuracy is satisfactory by the method and is of critical significance in obtaining up-to-date information of the sloping field, which should be helpful in the state key project of converting farmland to forest and grassland on slope land in this area. This research sought to improve the application accuracy of image classification in complex terrain areas.

关键词： remote sensing integrated classification loess hilly and gully area sloping field Shaanxi

在线全文

学校读者我要写书评

暂无评论

2022年度四川省苎麻精干麻质量分析报告

中国纤检 2024年第2期 52-53页

作者：王瑞杜龙齐翼朱天雯霍昱玲四川省纤维检验局、国家羽绒制品质量检验检测中心四川成都610000

2022年度四川省苎麻精干麻的质量分析,涉及单纤维细度、束纤维断裂强度、含油率、含胶率、白度及pH值等主要数据,全面分析2020年至2022年的各数据对比,给予质量提升建议,加强精细化管理,提高苎麻产品品质,加强质量监管,发挥公证检验助... 详细信息

2022年度四川省苎麻精干麻的质量分析,涉及单纤维细度、束纤维断裂强度、含油率、含胶率、白度及pH值等主要数据,全面分析2020年至2022年的各数据对比,给予质量提升建议,加强精细化管理,提高苎麻产品品质,加强质量监管,发挥公证检验助推作用。

关键词：苎麻精干麻单纤维细度束纤维断裂强度含油率含胶率白度 pH值

经血间充质干细胞外泌体对人卵巢癌细胞A2780生物学行为的影响

在线全文

学校读者我要写书评

暂无评论

中国医学前沿杂志（电子版） 2024年第2期16卷 50-57页

作者：陆茜林丁娜贺红林袁怡君贺天文冯露田超刘康李均川北医学院第二临床医学院(南充市中心医院)妇科四川南充637000 川北医学院第二临床医学院(南充市中心医院)烧伤整形美容外科四川南充637000 川北医学院第二临床医学院(南充市中心医院)组织工程与干细胞研究所四川南充637000

目的探讨经血源性间充质干细胞(menstrual blood-derived mesenchymal stem cells,MenSCs)来源的外泌体(MenSCs-derived exosomes,MenSCs-Exos)对人卵巢癌细胞A2780增殖、迁移、侵袭能力和细胞周期分布的影响和机制。方法分离纯化MenSCs,流式细胞术鉴定其细胞表型,油红O染色观察其成脂分化能力;超速离心法分离MenSCs-Exos,电子显微镜观察外泌体形态,纳米颗粒追踪分析其大小及分布,蛋白免疫印迹法检测外泌体标志性蛋白分子CD9、TSG101、calnexin的表达。采用CCK-8实验、划痕实验、Transwell细胞体外侵袭实验、流式细胞仪检测MenSCs-Exos对A2780细胞增殖、迁移、侵袭能力和细胞周期分布的影响;蛋白免疫印迹法检测Wnt/β-catenin信号通路相关蛋白和迁移相关蛋白的表达。结果成功分离具有干细胞表型和成脂分化潜能的MenSCs,同时检测发现MenSCs-Exos为边缘清晰、大小分布均匀的膜性囊泡,粒径为30~150 nm,平均为72.89 nm,膜表面标志性蛋白CD9、TSG101表达呈阳性,calnexin表达呈阴性。与对照组相比,MenSCs-Exos能增强A2780细胞增殖、迁移和侵袭能力,影响其细胞周期分布,并且可上调β-catenin、c-Myc、TCF4、Cyclin D1、Vimentin、N-cadherin的表达,下调E-cadherin的表达。结论 MenSCs-Exos可能是通过激活Wnt/β-catenin信号通路促进A2780细胞增殖,并通过下调E-cadherin的表达促进A2780细胞的迁移和侵袭。

关键词：外泌体经血源间充质干细胞卵巢癌 Wnt/β-catenin信号通路

Reflections on the system of evaluation of gene-edited livestock

在线全文

学校读者我要写书评

暂无评论

Frontiers of Agricultural Science and Engineering 2020年第2期7卷 211-217页

作者： Ziyao FAN tianwen WU Kui WU Yulian MU Kui LI State Key Laboratory of Animal Nutrition Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China

The rapid development of biotechnology has provided a greater understanding of the biological functions of major candidate genes that have important functions regarding economic traits,and new materials for livestock breeding have been obtained through gene editing(GE)and embryo manipulation with the purpose of improving quality and output and reducing the costs and risk of *** concerns,particularly over safety risks and production performance,must be *** is the most important component of the regulation of gene-edited livestock and is a crucial guarantee of public safety before the marketing of geneedited animal ***,the system of evaluation of gene-edited livestock is discussed in terms of public safety and production *** search for safe and ethical applications in the GE of livestock,a case-by-case evaluation strategy,and classification and simplification are used in order to promote a more efficient,objective,comprehensive and operable evaluation system.

关键词： evaluation gene editing livestock performance safety