预负荷系数对三油楔径向滑动轴承稳定性的影响

以三油楔径向滑动轴承为研究对象,采用M atlab语言进行编程,对二维R eyno lds方程离散化数值求解,探讨了预负荷系数对三油楔径向滑动轴承稳定性的影响。得出了三油楔径向滑动轴承稳定性在不同偏心率和宽径比下随轴承预负荷系数的变化而变化的一系列规律性曲线,并进行了理论分析。     

小儿呼吸道异物的诊治

目的提高小儿呼吸道异物诊疗水平。方法对1984～2004年32例小儿呼吸道异物的误诊误治病例进行分析。结果误诊误治的病种有:急性喉炎、急性喉气管炎、急性支气管炎、肺炎、肺脓肿、喉及气管肿瘤等。结论体征不典型,询问病史不仔细及有些医生对其认识不足是小儿呼吸道异物误诊误治的主要原因。     

Foreign body granuloma around implantable pulse generator for deep brain stimulation: Two case reports

We report two cases of granuloma that occurred around an implantable pulse generator (IPG) for deep brain stimulation. Both cases showed no signs of infection and disappeared after moving the IPG and removing the granulation. If a noninfectious mass is formed, the relocation of IPG may improve it.     

Foreign nurse importation and the supply of native nurses

The importation of foreign registered nurses has been used as a strategy to ease nursing shortages in the United States. The effectiveness of this policy depends critically on the long-run response of native nurses. We examine the effects of immigration of foreign-born registered nurses on the long-run employment and occupational choice of native nurses. Using a variety of empirical strategies that exploit the geographical distribution of immigrant nurses across US cities, we find evidence of large displacement effects – over a ten-year period, for every foreign nurse that migrates to a city, between 1 and 2 fewer native nurses are employed in the city. We find similar results using data on nursing board exam-takers at the state level – an increase in the flow of foreign nurses significantly reduces the number of natives sitting for licensure exams in more dependent states relative to less dependent states. Using data on self-reported workplace satisfaction among a sample of California nurses, we find suggestive evidence that part of the displacement effects could be driven by a decline in the perceived quality of the workplace environment.     

An unusual sharp magnetic foreign body in the oesophagus and its removal: A case report

Ingestion of foreign bodies is a common pediatric problem. The majority of ingested foreign bodies pass spontaneously. Oesophageal foreign bodies should be urgently removed because of their potential to cause complications. Ingested batteries that lodge in the oesophagus, sharp or pointed foreign bodies in the oesophageal or gastric tract, and ingestion of multiple magnets all require urgent endoscopic removal. A 4-year-old boy ingested a sharp magnetic foreign body, which was removed via rigid oesophagoscopy without complication. To the best of our knowledge, this is the only sharp magnetic foreign body ingested by a young child ever reported in the English-language literature. We describe the presentation and therapeutic procedure adopted in this case.     

THE APARTMENT

This article describes a remotivation experiment in one nursing home that has been very successful. Elements of The Apartment include a separate day room exclusively for those regressed female residents needing remotivation; an all-day program for those residents; and a variety of program offerings within The Apartment to intrigue and stimulate the participants.     

失衡与治理:学术期刊数字出版产业链利益分配问题研究

【目的】 探讨学术期刊数字出版产业链中的市场主体利益分配失衡问题的解决方案,以满足各方的合理利益诉求。【方法】 运用文献法、个案研究法等,对我国学术期刊数字出版产业链上、中、下游市场主体之间利益分配失衡的现状及原因进行分析。【结果】 数据库平台企业的双边市场地位与商业模式、学术期刊数字出版产品特性与收费模式、主管部门监管不到位、行政力量推动下的非完全市场化运行机制、版权维护动力不足,以及尊重知识产权意愿不强是当前学术期刊数字出版产业链利益分配失衡的主要原因。【结论】 充分发挥主管单位与行业协会监管职能、对数据库平台企业进行改革、引入区块链技术、构建基于版权保护的利益分配机制等是平衡各方利益的有效对策。     

新形势下我国科技期刊稿源变化趋势——面向作者和科技期刊编辑的问卷调查与分析

【目的】 分析科技评价体系改革和国家大力扶持期刊发展新形势下我国科技期刊稿源动态变化趋势,助力国内科技期刊加速发展。【方法】 针对作者和科技期刊编辑分别设计了“国内科技期刊作者投稿意愿调查”和“2020年国内科技期刊稿源情况调查”问卷,利用问卷星提供的问卷设计和问卷发放(借助科研、期刊交流微信群)、统计分析等功能完成问卷调查。【结果】 大多数(86.2%)期刊2020年的投稿量比2019年增加,但增加1倍以上的期刊仅占6.4%;大部分期刊稿件平均质量有所提高(49.4%)或基本持平(47.0%)。绝大多数作者比较认可中国科技期刊,但同时对期刊发文速度、审稿质量、传播力度等有越来越高的要求,对期刊服务能力、品牌特色有越来越多的期待。【结论】 科技评价体系改革和国家扶持期刊发展为中国科技期刊发展带来了机遇和挑战,面对作者投稿国内期刊意愿的变化,我国科技期刊应该采取更加积极的应对措施,稳步扩大出版量、优化出版流程以承载更多回流的优秀稿件。