Changes of air quality during the pandemic and airborne transmission issues

The COVID-19 pandemic has killed more than 1 000 000 people within nine months in 2020. The world is changed as the cities were locked down, the traffic reduced, and people forced to work from home and keep social distance. These controlling measures also resulted in drastic reduction of the emission of many air pollutants, providing researchers an unprecedented large-scale natural experiment in examining how the air quality would respond to a strong forcing. In this panel discussion held on 22 September 2020, five experts gathered to discuss their observations and analyses, as well as the current understanding and misconception about airborne transmission.This Forum article is dedicated to Prof. Martin Williams of the Imperial College London, who intended to join the panel discussion but passed away one day before it. Guy Brasseur Professor of Max Planck Institute for Meteorology, Germany Junji Cao Professor of Institute of Earth Environment, Chinese Academy of Sciences, China Aijun Ding Dean and Professor of School of Atmospheric Sciences, Nanjing University, China Lidia Morawska Professor of Queensland University of Technology, Australia Tong Zhu (Chair) Dean and Professor of College of Environmental Sciences and Engineering, Peking University, China     

跨界搜寻与大数据能力协同作用下平台企业商业模式创新研究

[目的/意义]开放式创新背景下,平台企业所处的市场竞争越来越激烈,平台同质化严重,平台企业内部所拥有的创新资源、创新能力不足,无法有效支撑企业商业模式创新。跨界搜寻与大数据能力的协同作用能够为平台企业商业模式创新提供有力支撑。[方法/过程]对跨界搜寻、大数据能力及商业模式创新相关文献进行梳理,基于平台企业商业模式构成要素,构建跨界搜寻与大数据能力协同作用模型。[结果/结论]跨界搜寻有助于创新知识流动和创新资源获取,大数据能力可以完成资源整合及深度分析,二者的协同作用可以促进市场新知识发现,有利于平台企业商业模式创新。     

The neutrophil-lymphocyte ratio to predict poor prognosis of critical acute myocardial infarction patients: a retrospective cohort study

IntroductionInflammation is closely related to adverse outcomes of acute myocardial infarction (AMI). This study aimed to evaluate whether neutrophil-lymphocyte ratio (NLR) can predict poor prognosis of critical AMI patients.Materials and methodsWe designed a retrospective cohort study and extracted AMI patients from the “Medical Information Mart for Intensive Care-III” database. The primary outcome was 1-year all-cause mortality. The secondary outcomes were 90-day and in-hospital all-cause mortalities, and acute kidney injury (AKI) incidence. The optimal cut-offs of NLR were picked by X-tile software according to the 1-year mortality and patient groups were created: low-NLR (< 4.8), high-NLR (4.8 - 21.1), and very high-NLR (> 21.1). Cox and modified Poisson regression models were used to evaluate the effect of NLR on outcomes in critically AMI patients.ResultsFinally, 782 critical AMI patients were enrolled in this study, and the 1-year mortality was 32% (249/782). The high- and very high-NLR groups had a higher incidence of outcomes than the low-NLR group (P < 0.05). The multivariate regression analyses found that the high- and very high-NLR groups had a higher risk of 1-year mortality (Hazard ratio (HR) = 1.59, 95% CI: 1.12 to 2.24, P = 0.009 and HR = 1.73, 95% CI: 1.09 to 2.73, P = 0.020), 90-day mortality (HR = 1.69, 95% CI: 1.13 to 2.54, P = 0.011 and HR = 1.90, 95% CI: 1.13 to 3.20, P = 0.016), in-hospital mortality (Relative risk (RR) = 1.77, 95% CI: 1.14 to 2.74, P = 0.010 and RR = 2.10, 95% CI: 1.23 to 3.58, P = 0.007), and AKI incidence (RR = 1.44, 95% CI: 1.06 to 1.95, P = 0.018 and RR = 1.34, 95% CI: 0.87 to 2.07, P = 0.180) compared with low-NLR group. NLR retained stable predictive ability in sensitivity analyses.ConclusionBaseline NLR is an independent risk factor for 1-year mortality, 90-day mortality, in-hospital mortality, and AKI incidence in AMI patients.     

既有运营车站改造施工技术

结合马嘎车站站场改造实例,详细介绍站场改造的技术准备、施工方案、缩短封锁时间技巧、道岔整修,确保在封锁时间内完成施工任务,为今后站场改造施工组织提供借鉴。     

一种自适应遗传算法对Hopfield网络权值的优化

针对Hopfield网络在求解优化问题中学习效率低,收敛速度慢,容易陷入局部最优等缺点和不足,把遗传算法同Hopfield网络结合起来,形成进化神经网络,对网络权值进行优化,并且通过对算法的讨论,说明该算法的有效性。     

图书馆普通员工职业胜任力研究主报告

本研究采用定性与定量相结合的方法,探索我国图书馆普通员工的职业胜任力特征.在专家访谈和关键事件行为访谈基础上,编制“图书馆员自我评价问卷”,并以此为测量工具在全国范围内实施问卷调查.根据对2799个有效样本的统计分析,建立我国图书馆普通员工职业胜任力模型和胜任力测评量表,阐释图书馆普通员工职业胜任力及其子维度的表现特征,探讨个人、教育、工作等因素对胜任力的影响,以及胜任力对工作满意度、离职倾向和组织承诺3个绩效指标的预测作用.     

网格技术及其安全架构

本文简要分析了网格技术及其对安全的要求,阐述了安全认证策略和网格的安全基础架构。并预测了网格的应用前景。     

自动化技术条件下的图书馆统计分析系统

主要论述了图书馆自动化管理系统进行统计分析时所面临的一些问题,并结合自己的工作经验探索解决的思路,以期与大家共同关注和交流图书馆统计分析工作。     

个性化信息服务系统的评估

分析了网络环境下信息资源管理的现状以及用户信息需求的特点,指出了以个性化信息服务系统为支撑提供个性化信息服务,并从用户的视角提出了评估个性化信息服务系统的若干指标。