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981.
The present experiment determined whether associative strength based upon 15 CS-US pairings at various interstimulus intervals (ISIs) could survive shifts of the ISI to influence the subsequent acquisition of the nictitating membrane (NM) CR. The choice of 15 preshift pairings was based upon previous work, which had shown that this training level produced substantial associative strength without NM CR acquisition. Consequently, this experiment, by shifting the ISI before the beginning of CR acquisition, served as an extension to traditional ISI-shift studies that have imposed the manipulation after CR acquisition. The findings of the experiment indicated that 15 preshift pairings in Stage 1 at ISIs from 250 to 4,000 msec were as effective as 15 pairings at a 500-msec ISI in determining the number of trials to the first NM CR in Stage 2 in which the training ISI was 500 msec. Moreover, 15 pairings in Stage 1 at ISIs from 250 to 2,000 msec were equivalent to 15 pairings at 500 msec in controlling the number of trials to 10 successive NM CRs in Stage 2. These outcomes demonstrate that, within a large ISI range, the associative strength based upon relatively few pairings is preserved despite various shifts of the ISI. Therefore, these results suggest that the reductions in CR performance, which have been consistently observed in traditional studies following ISI shifts, are not due to the loss of associative strength. 相似文献
982.
983.
社会工作是一项助人自助的专业活动,它帮助个人、群体、社区提高或恢复其社会功能,并创造有利于它们的社会环境。专业性的体育服务是社会工作中的重要内容,社区居民对体育咨询和指导的旺盛需求催生了社会体育指导员这一特殊职业。社会体育专业的学生要成为一名合格的社会工作者,必须具备自如的知识驾驭能力、良好的沟通能力、流畅的表达能力和果敢的决策能力以及服务意识、协作意识和创新意识。 相似文献
984.
This paper discusses procedures for the analysis of instructional strategies incorporated into distance learning materials, especially with regard to the development of the higher order cognitive ability—critical thinking. It examines the function of task analysis as an integral part of the instructional design process, analysing three different approaches available to the instructional designer towards the analysis of tasks required of distance learners. Comparing the learning hierarchy, the concept hierarchy, and the information processing approaches, it was found that the latter was the only one suitable for this current study because of the requirement that critical thinking be linked with domain‐specific knowledge, rather than be learned as an independent ability. Different algorithms for both the student and the designer/analyst are included as part of the information processing approach, and, although these methods are yet to be validated, they seem to offer sufficient promise, while allowing the analyst to make further decisions during the analysis. 相似文献
985.
This article focuses on the four primary issues that directly affect service delivery to students with learning disabilities in postsecondary settings, including (a) How are high school and post-secondary settings different? (b) How are eligibility and access determined? (c) How are reasonable accommodations determined? and (d) How can the independence level of college students with learning disabilities be fostered? Each of these issues will be discussed within the context of the student's transition from high school, where Public Law 94-142 is in effect, to college, where Section 504 of the Rehabilitation Act of 1973 applies. 相似文献
986.
以质粒pSC101为载体,用鸟枪法将短小芽孢杆菌A3染色体的β—内酰胺酶基因,克隆至大肠杆菌HB101。经质粒检测及酶切电泳分析证明,克隆的β—内酰胺酶基因位于2.6kb的EcoRI片段上,将此片段连接到质粒PAL32转化枯草杆菌,亦能表达并向胞外分泌β—内酰胺酶。 相似文献
987.
This study investigated the hypothesis that prompting students to self-assess their interest and understanding of science concepts and activities would increase their motivation in science classes. Students were randomly assigned to an experimental condition that wrote self-assessments of their competence and interest in science lessons or a control condition that wrote summaries of those same lessons. Writing activities were 10?min long and were given approximately once a week for eighteen weeks. Student motivation was assessed via self-report surveys for achievement goals and interest in science before and after the intervention. Students in the experimental condition showed higher endorsement of mastery goals and reported greater situational interest in science topics after the intervention compared to students who summarised the lessons. Increases in situational interest predicted higher individual interest in the domain. Results indicate an instructional practice requiring just 3?hours out of a semester of instruction was sufficient to achieve these effects on motivation in science classes. 相似文献
988.
论法律漏洞存在的原因、类型及其防治 总被引:1,自引:0,他引:1
法律漏洞指法律中的缺漏和矛盾。其存在有两个原因:法律自身及其调整的社会关系方面的原因和立法者方面的原因。法律漏洞可分为形式漏洞与实质漏洞。可从两方面消除或减少它:立法角度防止其产生和司法角度弥补。法律中存在漏洞虽影响法律的效度和信度,但对法制的完备也有重要作用。 相似文献
989.
本文基于学习《邓小平文选》第三卷的体会,试图从开放性、开拓性、独立性、辩证性、唯实性和群众性等六个方面剖析邓小平理论的时代特色,对建设有中国特色社会主义的理论和实践具有深刻的教益和启义。 相似文献
990.
If freezing underlies barpress conditioned suppression, then it seems odd that auditory cues paired with shock evoke more freezing than do visual cues, yet evoke similar suppression. Bevins and Ayres (1992) found that auditory and visual cues also evoked similar withdrawal from the bar and dipper areas and suggested that such withdrawal could explain the similar suppression. Seeking to understand that withdrawal, we found evidence in the present study that it was due either to adventitious punishment or to place-aversion learning. The cue for shock seemed to set the occasion for such learning. For example, we found that, as training progressed, rats’ tendency to leave the bar area during the cue first increased, then decreased, then increased again, reflecting, presumably, shock occurrence first inside, then outside, then inside the bar area again. Despite these changes in the rats’ location, barpress suppression remained stable, implying that leaving the bar area, though sufficient for barpress suppression, is unnecessary. 相似文献