视频公开课节目制作要求使用多机位进行拍摄制作,传统多机位制作多是用现场切换进行一次性录制制作,这种制作方式有前期工作量大,后期编辑不方便等缺点,本文结合具体案例,介绍了视频公开课多机位制作的流程,以及苹果公司后期制作软件Fin...视频公开课节目制作要求使用多机位进行拍摄制作,传统多机位制作多是用现场切换进行一次性录制制作,这种制作方式有前期工作量大,后期编辑不方便等缺点,本文结合具体案例,介绍了视频公开课多机位制作的流程,以及苹果公司后期制作软件Final Cut Pro X的多机位编辑技术。展开更多
目的:研究乙肝病毒X蛋白(hepatitis B virus X protein,HBX)对Gankyrin表达水平的影响以及Wnt/β-catenin信号通路在HBX基因调控Gankyrin表达中的作用。方法:HBX腺病毒表达载体(Ad-HBX-GFP)感染转染2种人肝癌细胞系HepG2、SMMC-7721细胞...目的:研究乙肝病毒X蛋白(hepatitis B virus X protein,HBX)对Gankyrin表达水平的影响以及Wnt/β-catenin信号通路在HBX基因调控Gankyrin表达中的作用。方法:HBX腺病毒表达载体(Ad-HBX-GFP)感染转染2种人肝癌细胞系HepG2、SMMC-7721细胞,Si-HBX分子(Si-HBX oligo)用LipofectamineTM 2000转染入HepG2.2.15细胞,用RT-PCR和Western blot法检测HBX与Gankyrin的表达情况;β-catenin腺病毒载体转染HepG2、SMMC-7721细胞,用Western blot法检测β-catenin与Gankyrin的表达情况;在沉默β-catenin表达的HepG2、SMMC-7721细胞中过表达HBX基因,Western blot法检测β-catenin与Gankyrin的表达情况。结果:①HepG2.2.15细胞中Gankyrin mRNA与蛋白表达水平均高于HepG2细胞(P<0.05)。②HepG2与SMMC-7721细胞系中Ad-HBX-GFP组Gankyrin mRNA与蛋白表达水平均高于绿色荧光蛋白腺病毒表达载体(Ad-GFP)组(P<0.01)。③HepG2.2.15细胞中Si-HBX组Gankyrin mRNA与蛋白表达水平均低于Si-阴性对照(Si-NC)组(P<0.01)。④在HepG2与SMMC-7721细胞系中过表达HBX后,Ad-HBX-GFP组β-catenin的蛋白表达水平均高于Ad-GFP组(P<0.01)。⑤在HepG2与SMMC-7721细胞系中过表达β-catenin后,β-catenin腺病毒表达载体(Ad-β-catenin-GFP)组Gankyrin的蛋白表达水平均高于Ad-GFP组(P<0.01)。⑥在HepG2与SMMC-7721细胞系中沉默β-catenin后,过表达HBX基因,Si-β-catenin腺病毒表达载体(Ad-si-β-catenin-RFP)组与红色荧光蛋白腺病毒表达载体(Ad-RFP)组相比,Gankyrin的蛋白表达水平未见升高(P<0.01)。结论:HBX-Wnt/β-catenin-Gankyrin信号转导通路存在与肝癌细胞中,抑制β-catenin的功能可阻遏HBX对Gankyrin的上调作用,本结果将可能为肝癌的治疗提供新的思路。展开更多
Pr0.6-x NdxCa0.4 FeO3-δ （ x = 0.0, 0.2, 0.3, 0.4, 0.5, 0.6） were synthesized using Pechini method. A number of studies were conducted concerning composition, specific area, crystalline structure and microstructure ...Pr0.6-x NdxCa0.4 FeO3-δ （ x = 0.0, 0.2, 0.3, 0.4, 0.5, 0.6） were synthesized using Pechini method. A number of studies were conducted concerning composition, specific area, crystalline structure and microstructure of the samples by means of FT-IR, BET, XRD TG-DTA and SEM. The results show that all the samples with different doping amounts of Pr^3＋ and Nd^3＋ on A-site are fine dispersed, and mean particle size less than 100 nm. The powders have good sinterability, and the relative density is 95% after sintered at 1200 ℃ for 2 h. It is found that all specimens are entirely single phase solid solutions with orthorhombic perovskite structure, the stable perovskitetype phase is formed completely after calcination at 900 ℃.展开更多
Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is nam...Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is named Χ(Chi)-Pro Milestone and supports four types of questions, namely: Multiple-choice, True/False, Short-Answer and Free-Response Essay questions. The study is motivated by the fact that student number in schools and universities is continuously growing at high, non-linear, and uncontrolled rates. This growth, however, is not accompanied by an equivalent growth of educational resources (mainly: instructors, classrooms, and labs). A direct result of this situation is having relatively large number of students in each classroom. It is observed that providing and using online-examining systems could be intractable and expensive. As an alternative, paper-based exams can be used. One main issue is that manually produced paper-based exams are of low quality because of some human factors such as instability and relatively narrow range of topics [1]. Further, it is observed that instructors usually need to spend a lot of time and energy in composing paper-based exams with multiple forms. Therefore, the use of computers for automatic production of paper-based exams from question banks is becoming more and more important. Methodology: The design and evaluation of X-Pro Milestone are done by considering a basic set of design principles that are based on a list of identified Functional and Non-Functional Requirements. Deriving those requirements is made possible by developing X-Pro Milestone using the Iterative and Incremental model from software engineering domain. Results: We demonstrate that X-Pro Milestone has a number of excellent characteristics compared to the exam-preparation and question banks tools available in market. Some of these characteristics are: ease of use and operation, user-friendly interface and good usability, high security and protection of the question bank-items, high stability, and reliability. Further, X-Pro Milestone makes initiating, maintaining and archiving Question-Banks and produced exams possible. Putting X-Pro Milestone into real use has showed that X-Pro Milestone is easy to be learned and effectively used. We demonstrate that X-Pro Milestone is a cost-effective alternative to online examining systems with more and richer features and with low infrastructure requirements.展开更多
文摘Pr0.6-x NdxCa0.4 FeO3-δ （ x = 0.0, 0.2, 0.3, 0.4, 0.5, 0.6） were synthesized using Pechini method. A number of studies were conducted concerning composition, specific area, crystalline structure and microstructure of the samples by means of FT-IR, BET, XRD TG-DTA and SEM. The results show that all the samples with different doping amounts of Pr^3＋ and Nd^3＋ on A-site are fine dispersed, and mean particle size less than 100 nm. The powders have good sinterability, and the relative density is 95% after sintered at 1200 ℃ for 2 h. It is found that all specimens are entirely single phase solid solutions with orthorhombic perovskite structure, the stable perovskitetype phase is formed completely after calcination at 900 ℃.
文摘Aims: This study aims at designing and implementing syllabus-oriented question-bank system that is capable of producing paper-based exams with multiple forms along with answer keys. The developed software tool is named Χ(Chi)-Pro Milestone and supports four types of questions, namely: Multiple-choice, True/False, Short-Answer and Free-Response Essay questions. The study is motivated by the fact that student number in schools and universities is continuously growing at high, non-linear, and uncontrolled rates. This growth, however, is not accompanied by an equivalent growth of educational resources (mainly: instructors, classrooms, and labs). A direct result of this situation is having relatively large number of students in each classroom. It is observed that providing and using online-examining systems could be intractable and expensive. As an alternative, paper-based exams can be used. One main issue is that manually produced paper-based exams are of low quality because of some human factors such as instability and relatively narrow range of topics [1]. Further, it is observed that instructors usually need to spend a lot of time and energy in composing paper-based exams with multiple forms. Therefore, the use of computers for automatic production of paper-based exams from question banks is becoming more and more important. Methodology: The design and evaluation of X-Pro Milestone are done by considering a basic set of design principles that are based on a list of identified Functional and Non-Functional Requirements. Deriving those requirements is made possible by developing X-Pro Milestone using the Iterative and Incremental model from software engineering domain. Results: We demonstrate that X-Pro Milestone has a number of excellent characteristics compared to the exam-preparation and question banks tools available in market. Some of these characteristics are: ease of use and operation, user-friendly interface and good usability, high security and protection of the question bank-items, high stability, and reliability. Further, X-Pro Milestone makes initiating, maintaining and archiving Question-Banks and produced exams possible. Putting X-Pro Milestone into real use has showed that X-Pro Milestone is easy to be learned and effectively used. We demonstrate that X-Pro Milestone is a cost-effective alternative to online examining systems with more and richer features and with low infrastructure requirements.
