L_(316)氮化钛不锈钢复合体胫骨内种植的动物实验研究

用真空离子镀技术在L316医用不锈钢表面镀上一层氨化钛薄膜,制成氮化钛-不锈钢复合体,并以纯钛及医用L316不锈钢作对照,植入60只小白鼠的胫骨内．经扫描电镜等观察结果表明：氮化钛-不锈钢复合体及纯钛材料与骨之间都形成骨整合及纤维整合界面,但是,氮化钛-不锈钢复合体比纯钛材料骨性结合界面形成早,成骨活跃     

The impact of student misconceptions on student persistence in a MOOC

Massive Online Open Courses (MOOCs) provide opportunities to learn a vast range of subjects. Because MOOCs are open to anyone with computer access and rarely have prerequisite requirements, the range of student backgrounds can be far more varied than in conventional classroom-based courses. Prior studies have shown that misconceptions have a huge impact on students' learning performance; however, no study has empirically examined the relationship between misconceptions and learning persistence. This study of 12,913 MOOC-takers examines how students' misconceptions about the upcoming course material affect course completion. Using a survival analysis approach, we found that, controlling for the score in a pre-course test, students holding more misconceptions had a higher dropout rate at the start of the course, an effect that diminished over time. Other student variables were found to have a positive impact on survival that persisted throughout the entire course: U.S. location, higher age, an intention to complete, better English skills, prior familiarity with the subject, motivation to earn a certificate, and score and time spent on the previous problem set (homework). By contrast, student gender, education level, number of previous MOOCs completed, and motivation to participate in online discussion forums did not affect survival.     

Teaching for social justice: A research synthesis on Asian American and Pacific Islander teachers in U.S. schools

This article examines social justice in teaching and teacher education with a focus on the experiences, pedagogies, and instructional practices of Asian American and Pacific Islander (AAPI) teachers. We synthesized 37 peer-reviewed research publications on AAPI teachers’ experiences and contributions to diversity and social justice. The results show AAPI teachers disrupting Whiteness through beliefs, pedagogies, and practices that value multiple perspectives and marginalized voices. Policy implications include supporting cultural and linguistic diversity in teacher education programs and schools and providing opportunities for teachers to engage in critical praxis regarding their racial identities and issues of equity in education.     

Game-Based Learning in Virtual Worlds: A Multiuser Online Game for Medical Undergraduate Radiology Education within Second Life

Game-based learning can have a positive impact on medical education, and virtual worlds have great potential for supporting immersive online games. It is necessary to reinforce current medical students' knowledge about radiological anatomy and radiological signs. To meet this need, the objectives of this study were: to design a competition-based game in the virtual world, Second Life and to analyze the students' perceptions of Second Life and the game, as well as to analyze the medium-term retention of knowledge and the potential impact on the final grades. Ninety out of 197 (45.6%) third-year medical students voluntarily participated in an online game based on self-guided presentations and multiple-choice tests over six 6-day stages. Participants and non-participants were invited to perform an evaluation questionnaire about the experience and a post-exposure knowledge test. Participants rated the experience with mean scores equal to or higher than 8.1 on a 10-point scale, highlighting the professor (9.5 ± 1.1; mean ± SD) and the virtual environment (8.9 ± 1.1). Participants had better results in the post-exposure test than non-participants (59.0 ± 13.5 versus 45.3 ± 11.5; P < 0.001) and a lower percentage of answers left blank (6.7 ± 8.4 versus 13.1 ± 12.9; P = 0.014). Competitive game-based learning within Second Life is an effective and well-accepted means of teaching core radiological anatomy and radiological signs content to medical students. The higher medium-term outcomes obtained by participants may indicate effective learning with the game. Additionally, valuable positive perceptions about the game, the educational contents, and the potential benefit for their education were discovered among non-participants.     

中华系列医学杂志学术质量控制机制应用现状调查

以中华医学会杂志社中华系列101种医学期刊作为调查对象,从公开编委会成员、责任编辑、利益冲突声明、作者贡献、原始数据和同行评审专家这6个方面切入,全面地了解目前这些医学期刊学术质量控制机制应用现状.     

主体的颠覆:拉康精神分析学中的"自我"

作为认识之主体的自我的身份无疑是哲学领域中的一个重大问题,但是这个问题在笛卡尔之前的本体论哲学中被视为不证自明的而放进了括号;认识论哲学将认识主体,也就是说将自我作为至关重要的问题提出来,但是最终还是将同一性和自主性赋予了它;语言论哲学的革命使人们得以重新思考这个问题,并对同一、自主的自我作了彻底的颠覆。但是,这种颠覆不是来自于形而上学,而是来自于拉康对弗罗伊德精神分析的创造性阐释。因为拉康的贡献,我们终于认识到,自我的同一和自主只是一种虚构和妄想,自我根本上是分裂的,因为自我其实就是一个他。自我的存在是为另一个人而建构的,建构的方式和结果使他像另一个人,而且其存在注定要被另一个人夺走。所以,自我的本质就是一种挫折。     

混合集成电路STR-S6708A工作原理

本文对电视机常用电源ICSTR-S6708A及开关电源工作原理进行了分析。     

英语学习过程诸因素探讨

在外语／二语学习过程中,必须充分考虑语言环境、社会语言环境、学习风格、学习年龄、学习阶段等因素,这些因素对学习者努力的结果有直接的决定性的影响。它们影响外语／二语学习者是否以及怎样充分利用可以得到的一切学习机会,而是否以及怎样充分利用可以得到的一切学习机会又决定外语／二语学习者能否学得目的语。外语／二语教师应该根据这些因素采取相应的教学策略和途径,来满足外语／二语学习者的学习需求。二语／外语教师在学习过程中的重要作用,体现于引导学习者以最适合自己学习风格的学习方法充分地有效地利用所能得到的二语／外语学习机会。     

浅谈Pro/REPOR自动生成产品设计明细表的方法

介绍了Pro/REPORT模块相关功能,着重阐述了利用Pro/REPORT功能模块自动生成产品设计明细表的方法,达到了提高明细表制作效率的目的。     

FH/SS通信系统抗干扰性能研究

介绍了跳频通信的基本原理,针对FH/SS通信系统非相干接收机模型,重点分析了FH/SS通信系统在宽带噪声干扰、部分频带干扰和多音干扰下的抗干扰性能分析,并进行仿真结果分析,结果显示FH/SS对宽带噪声的抗干扰性能最优。