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This study showed that during prime time, a new paradigm of gender role depiction has emerged in prime-time commercials in Japan, Taiwan, and Malaysia. Even though some stereotypes about the presentation of gender in commercials persist (for setting, product type, voice-over), the study found an equal number of males and females appearing as primary characters in commercials during prime time. In Japan, Malaysia, and Taiwan, the majority of commercials depicted males and females in nonstereotypical gender roles. Some shifts were also observed for role depiction in prime-time commercials in the United States. Reasons for these changes are discussed. 相似文献
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本研究运用模拟实验,考察了以仪表显示为主的监控系统中信号间隔时间和双作业任务对人觉察信号的反应时间的影响.双作业中的主任务是要求被试同时监视4个仪表,次任务为对显示屏上一个红色亮点是否出现闪烁作简单的辨别反应.实验结果表明信号间隔时间是影响信号觉察反应时的一个重要因素.随着信号间隔时间由30-50秒延长到8-10分钟,信号觉察反应时随之先快后慢地增加.在低负荷的仪表监视作业中,通过增加一个刺激率较高而又比较简单的次任务,可使被试保持较高的唤醒水平和更好地集中注意,从而有利于提高信号觉察效率. 相似文献
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上海市大中学生的心理健康及其与体育锻炼的关系 总被引:79,自引:1,他引:78
本研究利用《简式心境状态剖面图》(POMS)中国修订版和《运动力量等级量表—3》(PARS—3),对上海市大中学生的心理健康及其与体育锻炼的关系进行了考察。结果表明:①有较高比例的学生存在着不同程度的紧张、愤怒、疲劳、抑郁和慌乱,以及较低的精力和自尊感;②体育锻炼能有效地降低紧张、愤怒、疲劳、抑郁、慌乱,提高和自尊感,③中等到较大的运动量具有更好地心理健康效应;④体育乐趣与运动坚持性具有密切的关系。 相似文献
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Signaling Mechanisms Mediating BDNF Modulation of Synaptic Plasticity in the Hippocampus 总被引:8,自引:0,他引:8 下载免费PDF全文
Wolfram A. Gottschalk Hao Jiang Nicole Tartaglia Linyin Feng Alexander Figurov Bai Lu 《Learning & memory (Cold Spring Harbor, N.Y.)》1999,6(3):243-256
Although recent studies indicate that brain-derived neurotrophic factor (BDNF) plays an important role in hippocampal synaptic plasticity, the underlying signaling mechanisms remain largely unknown. Here, we have characterized the signaling events that mediate the BDNF modulation of high-frequency synaptic transmission. Mitogen-associated protein kinase (MAPK), phosphotidylinositol-3 kinase (PI3K), and phospholipase C-γ (PLC-γ) are the three signaling pathways known to mediate neurotrophin signaling in other systems. In neonatal hippocampal slices, application of BDNF rapidly activated MAPK and PI3K but not PLC-γ. BDNF greatly attenuated synaptic fatigue at CA1 synapses induced by a train of high-frequency, tetanic stimulation (HFS). Inhibition of the MAPK and PI3K, but not PLC-γ, prevented the BDNF modulation of high-frequency synaptic transmission. Neurotrophin-3 (NT-3), a close relative of BDNF, did not activate MAPK or PI3K and had no effect on synaptic fatigue in the neonatal hippocampus. Neither forskolin, which activated MAPK but not PI3 kinase, nor ciliary neurotrophic factor (CNTF), which activated PI3K but not MAPK, affected HFS-induced synaptic fatigue. Treatment of the slices with forskolin together with CNTF still had no effect on synaptic fatigue. Thus, although the activation of MAPK and PI3K is required, the two together are not sufficient to mediate the BDNF effect. Inhibition of new protein synthesis by anisomycin or cycloheximide did not prevent the BDNF effect. These data suggest that BDNF modulation of high-frequency transmission is independent of protein synthesis but requires MAPK and PI3K and yet another signaling pathway to act together in the hippocampus. 相似文献