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31.
InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal.  相似文献   
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固定资产是企业进行生产经营活动所必须拥有的劳动资料,因此对固定资产的管理非常重要。本文在认真比较新旧固定资产准则在定义、初始计量、后续支出等方面差异的基础上,分析了新《固定资产》准则的实施对企业的资产结构、利润和所有者权益等的影响。  相似文献   
33.
基于COM 组件技术的分布式开发方法是一个当前流行的软件设计方法,国外已有不少成功的应用系统开发案例,本文针对于南京理工大学经济管理学院MBA的实际情况,提出了基于COM 组件技术MBA网络教学管理系统的应用模型,并具体论述了系统的总体设计、功能结构设计及其实现。  相似文献   
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BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
36.
战略环境影响评价的理性范式思考   总被引:2,自引:0,他引:2  
SEA是以提高战略决策质量为目标的技术辅助工具,以标准化的程序方法模式来进行决策的环境影响识别、预测和评价,以物理环境的技术研究为侧重。然而,因为战略本身的复杂性和政治特征,有学者认为,SEA应该更侧重于提供不同利益团体共识达成的平台,在形式上具备对决策背景的可适应性和灵活性,不应该以标准化来僵化自身。有关两种模式的争论与目前学术界对工具理性、价值理性、非理性和交往理性的争论不无渊源。借用理性范式这个视角对SEA的两种模式进行深层思考,分析两种模式的各自长短之处,寻找互补的可能性,期望能够对SEA的发展提供可供借鉴的观点。  相似文献   
37.
国内语义Web研究综述   总被引:28,自引:3,他引:28  
田春虎 《情报学报》2005,24(2):243-249
语义Web并非一个独立的Web ,而是当前Web的延伸 ,其目标是让计算机能够“理解和处理”现在的Web仅仅能显示的数据 ,并为人们提供各种智能服务。目前在世界范围内对语义Web的研究尚处于起步阶段 ,与国外相比 ,我国对语义Web的研究相对较晚。本文试图对国内关于语义Web的研究做一简要的综述 ,在把握当前研究现状的基础上 ,明确今后主要的研究方向与重点问题。  相似文献   
38.
阐述了在Lib2.0时代,图书馆需求发生了重大变革,创新文献资源管理平台的管理模型刻不容缓。为适应我国城市区域性图书馆发展集成服务的需求和高校合并之后多馆管理的需求,提出从传统的单馆集中管理作业模式拓展到多馆分布管理及多馆集中分布式管理作业模式。调整了传统图书馆集成系统的作业流程,完善了相关功能,构建了动态的图书馆资源管理平台的管理模型,并进行了相关实践。  相似文献   
39.
提高科技期刊影响因子的途径探讨   总被引:17,自引:2,他引:17  
柳晓丽 《编辑学报》2006,18(4):285-286
分析科技期刊影响因子的主要影响因素,探讨提高科技期刊影响因子的途径.  相似文献   
40.
Background: Somali Bantu refugees, with unique health information needs, created challenges for health and social service providers. Objectives: A service innovation was developed (i) to raise awareness, especially among local health and social service providers, about the Bantu refugees’ presence in the community, their culture, and their information needs and (ii) to deliver needed health information, emphasizing child health, to the Bantu mothers in their homes. Methods: The project consisted of: (i) a community conference targeting local health and social service providers, describing the refugees’ presence in the community, their culture, and information needs. (ii) Focus groups conducted with members of the Bantu population elicited additional information needs. (iii) Curriculum was developed based on identified needs, and (iv) the curriculum was delivered to the refugees in their homes. A clinical informationist and MP3 technology enhanced the project. Findings: Conference attendees’ evaluation responses indicated improved understanding of Bantu culture. Focus groups’ identification of health information needs provided a framework for the health education curriculum. A project website made educational materials available to other healthcare providers. Conclusions: The project raised awareness of the Bantus’ presence, culture, and information needs. Identification of other unmet needs demonstrated that additional support for refugees is required.  相似文献   
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