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161.
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   
162.
This essay examines a set of memoranda, speeches, and other official discourse issued during the Global War on Terrorism that transformed the legal paradigm under which the enemy was defined and authorized new norms of conduct previously prohibited by law. It argues that these texts employ “deconstitutive rhetoric,” defined as discursive action that undermines the existing legal status of those to whom it refers and produces a disarticulate, destitute subject by denying the individual access to the civic forums in which rhetorical agency may be exercised. The essay begins with an analysis of the use of deconstitutive rhetoric in the decision to legally re-define Afghanistan as a “failed state” in order to absolve the United States of treaty obligations with that nation. It then addresses the emergence of “unlawful enemy combatant status,” a new legal category not recognized under the international laws of war. The essay concludes with a discussion the Obama administration’s detention and drone strike policies, which have continued to use deconstitutive rhetoric to undermine the legal status of those captured and killed in the Global War on Terrorism.  相似文献   
163.
论文通过借鉴和辨析社会学理论中的冲突概念,对师生冲突概念作出界定。根据美国当代社会学家刘易斯·科塞的冲突分类理论,对学校师生冲突进行分类研究。在此基础上提出了三个观点:学校师生冲突的多数属于非现实性冲突;师生结构由紧密走向松散是师生冲突增多的重要原因;师生冲突具有一定的正面功能。  相似文献   
164.
In the light of challenges arising from contemporary issues such as inclusivity, sustainability and justice, the connections between art, design and caring appears to be pertinent. What role can artists and designers play in the ecology of care? How can we lead art and design students to connect and lend their creative skills to care needs? Drawing on the ethics of care and a relational view on health this article highlights the various teaching approaches and initiatives introduced at Nanyang Technological University, Singapore, to support and guide students to realise various art and design for health and wellbeing projects that provide opportunities for students to part take in ecology of care using their creative skills. Although creative explorations at the intersection of art, design and caring is still at an early stage, outcomes from this ongoing effort have been encouraging in response to the shifting social needs to create a more inclusive and flourishing society in Singapore.  相似文献   
165.
Land degradation is one of the severe environmental problems in China. In order to combat land degradation, a soil conservation program was introduced since 2000 to reduce soil erosion by converting slope-cultivated land into forestry and pasture. This paper represents the first systematic attempt to investigate the impact of the soil conservation program on land degradation in the loess plateau. The results indicate that the soil conservation program to convert slope fields into forest or pasture is an effective way to combat soil erosion. However, a subsidy that is higher than profit of land use activity of slope fields before their conversion into forest and pasture is needed to encourage farmers to join the conservation program. A policy measure to encourage and assist farmers to develop sedentary livestock by using crops produced from fields as well as fodder and forage grass from the converted slope fields might contribute to combat soil erosion. Increase in off-farm job opportunities may encourage households to reduce cultivation in slope fields. That implies a policy measure to encourage rural urbanization might contribute to combat soil erosion.  相似文献   
166.
A synthesis of the commentaries to our leadoff paper is presented, along with our replies to some of the specific comments offered. When the original analysis and the commentaries are combined, an exceptionally thorough summary of issues that should be considered by intervention researchers emerges. We hope this set of issues will be useful to the educational research community.A draft of this synthesis was circulated among the commentators in this special issue, with a request to determine whether their views were represented fairly. There were few reservations expressed, and in every case when a concern was expressed, we concluded on review that slight adjustment was required to present the commentator's perspective more clearly and/or fairly, and we attempted to do so.  相似文献   
167.
In the course of a decade of research on learning in technology‐centered classrooms, my research group has gained considerable understanding of why and how students learn science by designing technology. In this article I briefly review two dimensions in which science and technology share fundamental similarities: (a) the production and transformation of representations and (b∥ the action‐oriented language describing the two domains. Because it is fundamentally problematic to derive what ought to happen in science classrooms from other dimensions, I provide three episodes to illustrate what and how students know and learn science during technological design activities. Episodes and analyses embody the two dimensions previously outlined. Because these episodes are representative of the database established during an extensive research program, I suggest there is sufficient ground for using and investigating science‐through‐technology curricula. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 768–790, 2001  相似文献   
168.
169.
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion.  相似文献   
170.
This investigation analyzed goals from the Individual Educational Programs (IEPs) of 54 high school students with diagnosed reading disabilities in basic skills (decoding and/or word identification). Results showed that for 73% of the students, the IEPs written when they were in high school failed to specify any objectives regarding their acute difficulties with basic skills. IEPs from earlier points in the students’ educations were also reviewed, as available. For 23 of the students, IEPs were present in the students’ files for three time points: elementary school (ES), middle school (MS), and high school (HS). Another 20 students from the sample of 54 had IEPs available for two time points (HS and either MS or ES). Comparisons with the IEPs from younger years showed a pattern of decline from ES to MS to HS in the percentage of IEPs that commented on or set goals pertaining to weaknesses in decoding. These findings suggest that basic skills deficits that persist into the upper grade levels are not being sufficiently targeted for remediation, and help explain why older students frequently fail to resolve their reading problems.  相似文献   
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