档案工作如何应对灾难的发生

灾难一般是自然原因、人为原因或二者综合引起的不期而至并且造成严重破坏的事件,可分为自然灾害和人为灾害两大类。自然灾害是由自然现象引起的,如地震、台风、火山爆发、洪水等;人为灾害则来自人类自身的破坏或失误,如纵火、爆炸、恐怖活动、战争等。正如一句谚语所说,“天有不测风云,人有旦夕祸福”,灾难具有随时发生而没有任何预警的特性。任何灾难发生前不会和我们打一声招呼,能让我们有足够的时间进行准备。因为不可能确切地知道灾难何时发生而它又会随时到来,所以,只有在平时投入一定力量加以防范,才能避免被突发灾祸打得一蹶不振。…     

翻转课堂中教学理答艺术探微

教学理答艺术是翻转课堂中的重要教学活动。教学艺术和信息技术的双重底蕴为教学理答艺术在翻转课堂中的运用增添了新的机遇和挑战。本文通过品读教学理答艺术的内涵,深刻认识教学理答艺术在翻转课堂中的运用价值,继而有效探索教学理答艺术在翻转课堂中的运用策略,以期打造更加高效和谐的翻转课堂。     

Measuring knowledge integration: Validation of four‐year assessments

Science education needs valid, authentic, and efficient assessments. Many typical science assessments primarily measure recall of isolated information. This paper reports on the validation of assessments that measure knowledge integration ability among middle school and high school students. The assessments were administered to 18,729 students in five states. Rasch analyses of the assessments demonstrated satisfactory item fit, item difficulty, test reliability, and person reliability. The study showed that, when appropriately designed, knowledge integration assessments can be balanced between validity and reliability, authenticity and generalizability, and instructional sensitivity and technical quality. Results also showed that, when paired with multiple‐choice items and scored with an effective scoring rubric, constructed‐response items can achieve high reliabilities. Analyses showed that English language learner status and computer use significantly impacted students' science knowledge integration abilities. Students who took the assessment online, which matched the format of content delivery, performed significantly better than students who took the paper‐and‐pencil version. Implications and future directions of research are noted, including refining curriculum materials to meet the needs of diverse students and expanding the range of topics measured by knowledge integration assessments. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 48: 1079–1107, 2011     

专题征稿增强科技类学术期刊对社会热点问题的响应

目前,科技类学术期刊对社会热点存在关注不足、响应不够的现实问题。结合《中国环境科学》对社会热点问题专题征稿的实践,总结出实施所需4方面内容:了解与期刊相关的社会热点问题、确立征稿范围、建立征稿的快速响应机制和按约定时间刊出。并对专题征稿成效及其成功与不足进行了反思和总结,以为其他科技期刊的社会热点问题征稿提供参考。     

DNA-damage response network at the crossroads of cell-cycle checkpoints,cellular senescence and apoptosis

Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycle, cellular senescence, apoptosis regulation, cancer development and tumor responses to cancer treatment has become eminently apparent. Extensive research on tumor suppressor genes, oncogenes, the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways, referred to as the DNA-damage response network, are tied to cell proliferation, cell-cycle arrest, cellular senescence and apoptosis. DNA-damage responses are complex, involving ＂sensor＂ proteins that sense the damage, and transmit signals to ＂transducer＂ proteins, which, in turn, convey the signals to numerous ＂effector＂ proteins implicated in specific cellular pathways, including DNA repair mechanisms, cell-cycle checkpoints, cellular senescence and apoptosis. The Bcl-2 family of proteins stands among ＂the mos＂t crucial regula＂tors of apop＂tosis and performs vi＂tal func＂tions in deciding whether a cell will live or die after cancer chemotherapy and irradiation. In addition, several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle, DNA repair/recombination and cellular senescence, effects that are generally distinct from their function in apoptosis. In this review, we report progress in understanding the molecular networks that regulate cell-cycle checkpoints, cellular senescence and apoptosis after DNA damage, and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.     

“丝绸之路经济带”干旱-半干旱区生态环境全球变化响应的空间认知

在高强度人类活动和全球变化的影响下,"丝绸之路经济带"的资源环境面临严峻问题与挑战。地处"丝绸之路经济带"核心区的中亚地区的生态环境退化已经上升为全球干旱地区生态环境问题突出地区之一,严重制约了中亚及周边国家的经济与社会发展。文章针对"丝绸之路经济带"核心区的中国新疆、中亚地区及周边区域的典型生态环境要素:植被要素和水资源要素,基于长时间序列的卫星遥感数据,研究和分析了其参数时空演进格局及对气候变化的响应。研究结果表明,中亚地区近几十年的生态环境总体上呈现退化趋势,具体表现为水储量减少、湖泊面积萎缩、地表土壤水分减少和植被退化等。     

A probe into EFL learners’ emotioncy as a source of test bias: Insights from differential item functioning analysis

The development of unbiased tests is crucial in the arena of language testing in order to ensure validity. To date, studies of bias in language testing have mainly focused on factors such as gender, native language, or academic background, inter alia. However, bias may also result from psychological factors. Therefore, the present study investigates the role of English as a Foreign Language (EFL) test takers’ emotioncy, defined as the emotions evoked by senses that one holds for an entity, in their test performance. Specifically, this study aimed to examine emotioncy for the form as well as the meaning of 20 words to find out whether it can lead to differential functioning of the items on a vocabulary test. To this end, two emotioncy scales and a vocabulary test were designed. Then, based on the data collected from 235EFL students, the participants were bisected into the Low-Group and the High-Group, once based on their emotioncy scores for each word form and then based on their emotioncy scores for each word meaning. Subsequently, Rasch model-based Differential Item Functioning (DIF) analysis was performed across the two groups. The results showed that the vocabulary test items functioned differentially across the two groups in both form and meaning classifications, favoring the High-Group. Therefore, the study provides evidence for emotioncy as a psychological source of test bias and discusses implications for language testing stakeholders.     

Electronic in-class course evaluations and future directions

This study sought to determine whether an evaluator conducting electronic course evaluations in person in a classroom increased response rates. At a large public university in the United States, course evaluations were being conducted electronically, attaining a response rate of <50% over several semesters. At the end of the Spring 2015 at this university, an evaluator entered several classrooms having a total enrollment of 273 students and guided students through the process of completing course evaluations using their mobile devices. A response rate of 78.4% was achieved. The process described in this study provides evidence that response rates can be increased in similar circumstances. In addition, several ways the technology described could be used in the future for course evaluation are discussed.     

PLC程序执行时序对控制结果的影响

可编程序逻辑控制器PLC是一种基于软件和硬件控制的工业现场计算机控制系统。在了解生产工艺和控制要求的基础上,设计系统程序时必须充分考虑到硬件的特性,编制出与硬件协调配合的程序,合理分配PLC软件程序执行时序,使控制系统能精确、稳定、快速工作。反之,则会出现一些意外故障,造成控制系统误动作。通过PLC控制电梯的部分梯形图...