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A GIS-based research on the distribution of rural settlements in Yulin of northern Shaanxi

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Journal of Geographical Sciences 2002年第2期12卷 48-53页

作者： ZHAO Mu-dan TANG Guo-an shi Wen-zhong LIU Yong-mei Dept. of Urban and Resources Northwest University Xi’an China Dept. of Land Survey and Geo-informatics The Hong Kong Polytechnic University Hong Kong China

The development and distribution pattern of rural settlements was greatly limited by their natural and social environment. Taking Yulin prefecture in northern Shaanxi抯 Loess Plateau area as an example, 1:250,000 map-scale national geographical database as a major information source, a GIS-based research was conducted to investigate the spatial distribution of the rural settlements. In this paper, many significant characteristics of the rural settlement distribution are reviewed by means of a series of GIS-based information processing methodology. The results obtained in this study should be helpful for the urban and rural settlements reconstruction planning in this area.

关键词： GIS rural settlement distribution Yulin prefecture

New Virus,New Challenge

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The Innovation 2020年第1期1卷 110-112页

作者： yi shi CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijingChina

The ongoing COVID-19 pandemic has made us to consider the emergence of potential viral diseases in the *** can carry vast and diverse virus species,most of which we do not understand yet,and the spillover events of the viruses from the unknown pool in animals to human population always occurred in the *** effectively prevent and control the emerging viral diseases,we should make efforts to explore the unknown virus species in nature and prepare in advance.

关键词： diseases carry diverse

GenOrigin: A comprehensive protein-coding gene origination database on the evolutionary timescale of life

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Journal of Genetics and Genomics 2021年第12期48卷 1122-1129页

作者： yi-Bo Tong Meng-Wei shi Sheng Hu Qian Yu-Jie Chen Zhi-Hui Luo yi-Xuan Tu Yu-Li Xiong ying-Jie Geng Chunyan Chen Zhen-Xia Chen Hubei Hongshan Laboratory College of Biomedicine and HealthHuazhong Agricultural UniversityWuhan 430070China Hubei Key Laboratory of Agricultural Bioinformatics College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Center for Ecological and Environmental Sciences Northwestern Polytechnical UniversityXi’an 710072China Interdisciplinary Sciences Institute Huazhong Agricultural UniversityWuhan 430070China Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityShenzhen 518000China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518000China

The origination of new genes contributes to the biological diversity of life. New genes may quickly build their network, exert important functions, and generate novel phenotypes. Dating gene age and inferring the origination mechanisms of new genes, like primate-specific genes, is the basis for the functional study of the genes. However, no comprehensive resource of gene age estimates across species is available. Here,we systematically date the age of 9,102,113 protein-coding genes from 565 species in the Ensembl and Ensembl Genomes databases, including 82 bacteria, 57 protists, 134 fungi, 58 plants, 56 metazoa, and 178 vertebrates, using a protein-family-based pipeline with Wagner parsimony algorithm. We also collect gene age estimate data from other studies and uniformly distribute the gene age estimates to time ranges in a million years for comparison across studies. All the data are cataloged into Gen Origin(http://***/), a user-friendly new database of gene age estimates, where users can browse gene age estimates by species, age, and gene ontology. In Gen Origin, the information such as gene age estimates,annotation, gene ontology, ortholog, and paralog, as well as detailed gene presence/absence views for gene age inference based on the species tree with evolutionary timescale, is provided to researchers for exploring gene functions.

关键词： Gene age Gene family Comparative analysis

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计算飞行力学的产生和发展

航空学报 2001年第1期22卷 1-5页

作者：关世义中国海鹰机电技术研究院北京100074

综述了计算飞行力学的产生背景、问题表述、理论框架和飞行力学的计算系统。

关键词：计算飞行力学产生背景理伦框架发展史

Promotion of the articular cartilage proteoglycan degradation by T-2 toxin and selenium protective effect

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第1期9卷 22-33页

作者： Si-yuan LI Jun-ling CAO zhong-li shi Jing-hong CHEN Zeng-tie ZHANG Clare E. HUGHES Bruce CATERSON Institute of Endemic Diseases College of Medicine Xi＇an Jiaotong University Key Laboratory of Environment and Genes Related to Diseases （Xi＇an Jiaotong University） Ministry of Education Kev Laboratory of Microelement and Endemic Disease （Xi＇an Jiaotong University） Ministr） of Health Xi＇an 710061 China Laboratory of Connective Tissue Biology School of Biosciences Cardiff University Cardiff CF10 3US UK

Objective: To identify the relationship between T-2 toxin and Kashin-Beck disease (KBD),the effects of T-2 toxin on aggrecan metabolism in human chondrocytes and cartilage were investigated in vitro. Methods: Chondrocytes were isolated from human articular cartilage and cultured in vitro. Hyaluronic acid (HA),soluble CD44 (sCD44),IL-1β and TNF-α levels in super-natants were measured by enzyme-linked immunosorbent assay (ELISA). CD44 content in chondrocyte membrane was deter-mined by flow cytometry (FCM). CD44,hyaluronic acid synthetase-2 (HAS-2) and aggrecanases mRNA levels in chondrocytes were determined using reverse transcription polymerase chain reaction (RT-PCR). Immunocytochemical method was used to investigate expressions of BC-13,3-B-3(-) and 2-B-6 epitopes in the cartilage reconstructed in vitro. Results: T-2 toxin inhibited CD44,HAS-2,and aggrecan mRNA expressions,but promoted aggrecanase-2 mRNA expression. Meanwhile,CD44 expression was found to be the lowest in the chondrocytes cultured with T-2 toxin and the highest in control plus selenium group. In addition,ELISA results indicated that there were higher sCD44,IL-1β and TNF-α levels in T-2 toxin group. Similarly,higher HA levels were also observed in T-2 toxin group using radioimmunoprecipitation assay (RIPA). Furthermore,using monoclonal antibodies BC-13,3-B-3 and 2-B-6,strong positive immunostaining was found in the reconstructed cartilage cultured with T-2 toxin,whereas no positive staining or very weak staining was observed in the cartilage cultured without T-2 toxin. Selenium could partly inhibit the effects of T-2 toxin above. Conclusion: T-2 toxin could inhibit aggrecan synthesis,promote aggrecanases and pro-inflammatory cytokines production,and consequently induce aggrecan degradation in chondrocytes. These will perturb metabolism balance between aggrecan synthesis and degradation in cartilage,inducing aggrecan loss in the end,which may be the initiation of the cartilage degradation.

关键词： T-2 toxin Kashin-Beck disease (KBD) Aggrecan IL-1β TNF-α Aggrecanase Hyaluronic acid (HA) CD44

The improvement of the logistics management in the modem enterprises

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International Journal of Technology Management 2013年第4期 10-12页

作者： yi shi Langfang Teachers University Langfang Hebei 065000 China

With the increasing development of the logistics industry in China, more and more enterprises increasingly emphasis on logistics management, and initially have made certain achievements in logistics management to carry out the majority of small and medium enterprises in China which is less than ideal. The logistics has great potential in reducing costs. This article discusses the mode of operation of the enterprise logistics management. And it has an important significance to constantly optimize enterprise logistics, to improve logistics management and the competitiveness of SMEs in China.

关键词： logistics management modem enterprises Supply chain management

基于自动规划的完备行动方案集生成及其在体系毁伤分析中的应用

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系统工程理论与实践 2012年第2期32卷 417-424页

作者：郑重毕义明第二炮兵工程学院基础部军事运筹教研组西安710025

提出使用自动规划研究作战体系的易损性.通过目标、能力、状态和行动对体系进行概念化描述,将体系的易损性分析转化为给定初始状态下体系目标的可达性判定和所有可能规划解的生成问题.修改了经典图规划算法的搜索策略,将与或图的搜索转... 详细信息

提出使用自动规划研究作战体系的易损性.通过目标、能力、状态和行动对体系进行概念化描述,将体系的易损性分析转化为给定初始状态下体系目标的可达性判定和所有可能规划解的生成问题.修改了经典图规划算法的搜索策略,将与或图的搜索转化为带有目标和动作节点的树的深度优先搜索.实现了不包含冗余动作意义下的完备行动方案集生成,证明了算法的可靠性和完备性.算法对于可选行动和行动前提都较少的情况具有较好的执行效率.算例说明算法用于体系易损性分析是可行的.但对于大规模问题,需要探索通过附加约束条件限制搜索规模的方法.

关键词：体系易损性自动规划图规划完备行动方案集

一种新型水尺计重无人船平台系统的设计及应用探索

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中国口岸科学技术 2024年第2期6卷 15-19页

作者：张忠义马赛男丁海涛曾欢周聪宁波海关宁波315000 中电科(宁波)海洋电子研究院有限公司宁波315000 镇海海关宁波315200

本文通过分析比较几种近年来广泛应用的智能装备搭载的智能识别技术,研发了一种新型无人船水尺观测平台,具有自主航行、遥控功能、深度学习和图像模糊识别的水尺智能识别装置,实现了全天候、智能化水尺计重,促进了水尺计重工作的发展,... 详细信息

本文通过分析比较几种近年来广泛应用的智能装备搭载的智能识别技术,研发了一种新型无人船水尺观测平台,具有自主航行、遥控功能、深度学习和图像模糊识别的水尺智能识别装置,实现了全天候、智能化水尺计重,促进了水尺计重工作的发展,提升了水尺计重工作的准确性。

关键词：水尺计重水下潜航无人船智能识别

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基于轮廓测量的牙膏磨损性测定法的研发概述

日用化学品科学 2024年第3期47卷 67-72页

作者：孙东方宋硕 Eva Schneiderman 王莉江施裔磊黑龙江省轻工科学研究院全国口腔护理用品标准化技术委员会牙膏分技术委员会黑龙江哈尔滨150010 北京宝洁技术有限公司北京101312 P&G Mason Business Center Mason OH 45040 上海美加净日化有限公司上海200333

牙膏中的磨料是提供牙膏清洁力的主要成分之一。恰当的磨料种类选择以及添加量的设定可以为消费者提供良好的牙齿清洁效果,甚至达到较佳的外源性色斑的去除而美白牙齿。然而,不当的磨料添加会导致过度磨损牙齿,从而引起安全性问题。因此... 详细信息

牙膏中的磨料是提供牙膏清洁力的主要成分之一。恰当的磨料种类选择以及添加量的设定可以为消费者提供良好的牙齿清洁效果,甚至达到较佳的外源性色斑的去除而美白牙齿。然而,不当的磨料添加会导致过度磨损牙齿,从而引起安全性问题。因此,制定方便有效的牙膏磨损性测定法一直是业界的需求。然而,由于实验条件等限制,国际上惯用的示踪法(RDA)无法在国内实施。本文介绍了一种优化后的基于轮廓仪测量法开发的RDA替代方法Radioactive Dentin Abrasivity–Profilometry Equivalent (简称RDA-PE),并对RDA-PE方法的建立、方法学验证以及与RDA方法间的关系进行了简要的介绍.。同时,对RDA-PE方法用于测定牙膏产品摩擦型性能的可行性进行了讨论。

关键词：牙膏磨损性示踪法轮廓测量法