激光斑纹反差测量乳状液颗粒大小     

孙程远 《衡阳师范学院学报》2002,23(6):23-26

本文首次实现了用斑纹反差方法测量乳状液颗粒大小及分散相折射率，具有高精度和高分辨率等优点。  相似文献   

An evaluation of outcomes following the replacement of traditional histology laboratories with self‐study modules          下载免费PDF全文

Andrew R. Thompson  Donald J. Lowrie Jr 《Anatomical sciences education》2017,10(3):276-285

Changes in medical school curricula often require educators to develop teaching strategies that decrease contact hours while maintaining effective pedagogical methods. When faced with this challenge, faculty at the University of Cincinnati College of Medicine converted the majority of in‐person histology laboratory sessions to self‐study modules that utilize multiple audiovisual modalities and a virtual microscope platform. Outcomes related to this shift were investigated through performance on in‐house examinations, results of the United States Medical Licensing Examination^® (USMLE^®) Step 1 Examination, and student feedback. Medical School College Admissions Test^® (MCAT^®) scores were used as a covariate when comparing in‐house examinations. Results revealed no significant change in performance on in‐house examinations when the content being assessed was controlled (F(2, 506) = 0.676, P = 0.51). A significant improvement in overall practical examination grade averages was associated with the self‐study modules (F(6, 1164) = 10.213, P < 0.01), but gradual changes in examination content may explain this finding. The histology and cell biology portion of USMLE Step 1 Examination remained consistent throughout the time period that was investigated. Student feedback regarding the self‐study modules was positive and suggested that features such as instructor narrated videos were an important component of the self‐study modules because they helped recreate the experience of in‐person laboratory sessions. Positive outcomes from the student perspective and no drop in examination performance suggests that utilizing self‐study modules for histology laboratory content may be an option for educators faced with the challenge of reducing contact hours without eliminating content. Anat Sci Educ 10: 276–285. © 2016 American Association of Anatomists.  相似文献   

黑客的入侵与安全性建设     

乐光学 《怀化学院学报》2002,21(5):63-67

对黑客入侵网络系统的方式与相应的防范措施进行了详细的理论分析和探讨 ,旨在为网络安全性建设提供理论参考 ,并提出了安全性建设的原则  相似文献   

Reasonable expectations of privacy     

Robert L. McArthur 《Ethics and Information Technology》2001,3(2):123-128

Use of the concept of `areasonable person and his or her expectations'is widely found in legal reasoning. This legalconstruct is employed in the present article toexamine privacy questions associated withcontemporary information technology, especiallythe internet. In particular, reasonableexpectations of privacy while browsing theworld-wide-web and while sending and receivinge-mail are analyzed.  相似文献   

不同运动负荷大鼠心脏血流动力学变化对左心室内皮细胞形态影响的实验研究   总被引：5，自引：1，他引：4  

田振军 《天津体育学院学报》1999,14(1):46-48

采用Ｓ－５７０型扫描电镜和ＲＭ－６２００多道生理记录仪观察分析了大鼠不同运动条件下的心脏血流动力学参数及左心室几何构型和内皮细胞形态变化。结果表明,一般运动负荷导致心脏发生生理性肥大,左心室血流动力学指标升高,左心室流出道内皮细胞由于壁面切应力作用呈流畅梭形,其排列方向与血流方向一致,左心室心尖部由于涡流及二次流作用,内皮细胞呈现卵石样外观,形态各异,排列无序;运动超负荷导致心脏肥大的同时左心室血流动力学指标降低,心脏发生缺血缺氧性损伤,左心室流出道内皮细胞过度拉伸,个别内皮细胞损伤,左心室心尖部内皮细胞损伤严重,红细胞及血小板粘附。提示运动超负荷左心室内皮细胞损伤的病理生理机制主要是由左室壁面切应力、涡流和血液淤滞及心内膜下缺血缺氧共同作用的结果  相似文献   

高效薄层色谱双波长扫描法测定冠心通脉灵片中葛根素的含量     

库尔班江  塞丽曼 《伊犁师范学院学报》1999,(4)

在硅胶G高效薄层色谱板上,采取双波长薄层扫描法测定了冠心通脉灵片中葛根素的含量.本法快速,简便,方法可靠,板简误差小,平均回收率为99.80%变异系数为1.39%.  相似文献   

Gravitational perturbation of hydrogen spectrum in the space curved by intense laser pulses     

Ji Peiyong Zhu Shitong * Shen Wenda 《上海大学学报(英文版)》1998,2(3):198-203

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A Web-Based Virtual Microscopy Platform for Improving Academic Performance in Histology and Pathology Laboratory Courses: A Pilot Study     

Bai-Chin Lee  Sung-Tsang Hsieh  Yih-Leong Chang  Fen-Yu Tseng  Yu-Jung Lin  Yuh-Lien Chen  Shu-Huei Wang  Yu-Fong Chang  Yi-Lwun Ho  Yen-Hsuan Ni  Shan-Chwen Chang 《Anatomical sciences education》2020,13(6):743-758

Virtual microscopy (VM) has been utilized to improve students' learning experience in microscope laboratory sessions, but minimal attention has been given to determining how to use VM more effectively. The study examined the influence of VM on academic performance and teacher and student perceptions and compared laboratory test scores before and after VM incorporation. A total of 662 third-year students studying histology and 651 fourth-year students studying pathology were divided into two groups. The light microscopy (LM) group used a light microscope in 2014 and 2015, while the LM + VM group used the VM platform and a light microscope in 2016 and 2017. Four factors positively predict laboratory scores (R square, 0.323; P < 0.001): (i) the pathology course and test-enhanced learning, (ii) the VM platform and experience, (iii) medical students and lecture scores, and (iv) female students. The LM + VM group exhibited less score variability on laboratory examinations relative to their mean than the LM group. The LM + VM group was also associated with fewer failing grades (F grade; odds ratio, 0.336; P < 0.001) and higher scores (A grade; odds ratio, 2.084; P < 0.001) after controlling for sex, school, course, and lecture grades. The positive effect of the VM platform on laboratory test grades was associated with prior experience using the VM platform and was synergistic with more interim tests. Both teachers and students agreed that the VM platform enhanced laboratory learning. The incorporation of the VM platform in the context of test-enhanced learning may help more students to master microscopic laboratory content.  相似文献   

原子反弹激光中的光放大     

徐立森  夏立新  杨国健 《湖南科技学院学报》2005,26(5):50-52

本文引入了一种介于普通激光和自由电子激光之间的光放大机制,然后对其进行数值模拟,揭示了光放大的本质,并讨论原子密度、气体介质体积等工作参数对光放大的影响,对原子反弹激光有很好的指导意义。  相似文献   

三维激光扫描系统的应用研究   总被引：3，自引：0，他引：3  

范海英 《辽宁科技学院学报》2009,11(2):34-35

本文就三维激光扫描成像系统的原理和发展趋势做了简要的叙述,以工程应用实例对三维激光扫描成像系统的工作流程和三维建模做了详细的说明,并对三维激光扫描系统采集的点云数据处理的方法和手段进行了研究。  相似文献