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81.
We examined the influence of semantic similarity and proactive interference (PI) on the word length effect (WLE) in immediate serial recall. Word length was manipulated by comparing memory for monosyllabic versus multisyllabic words. PI effects were evaluated by manipulating semantic similarity in the to-be-remembered lists and examining its impact on the WLE’s magnitude across eight-trial blocks. Words were sampled from a single semantic category across the entire block, from a single category within the list, or from different categories. Robust WLEs were observed in single-category blocks and when words were from different categories. However, when all the within-list words were from the same semantic category, the WLE was sharply attenuated. Except for the within-list semantic similarity condition, there was a buildup in PI levels in the form of protrusion errors across trials. However, the magnitude of the WLE did not increase with the PI buildup, suggesting that it was not affected by PI across trials.  相似文献   
82.
This exploratory study examined religious identity among Christian Korean-American adolescents. Marcia's 1966 model of identity formation, which conceptualizes identity along dimensions of exploration and commitment, provided the framework for the current study. 49 participants, between the ages of 14 and 19 years, completed the Duke Religion Index, the religion items from the Extended Objective Measure of Ego Identity Status, the Pan-denominational Measure of Personal Devotion and Personal Conservatism, and six questions assessing perceived parental involvement. Analysis indicated that high scores on Organizational and Intrinsic Religiosity were positively correlated with the commitment statuses of Achievement and Foreclosure and negatively correlated with the noncommitment statuses of Moratorium and Diffusion. Also high scores on perceived parental involvement were positively correlated with the nonexploration status of Foreclosure and negatively correlated with the exploration status of Moratorium. Overall, the study provided a general portrait and initial examination of the formation of religious identity in a sample of Christian Korean-American adolescents.  相似文献   
83.
Three studies found that prospective temporal self-appraisals can be part of defensive pessimists' strategy; they felt closer to equally distant negative than positive futures. In Study 1, defensive pessimists felt closer to future failures and reported more negative affect than those considering success. In Study 2, when manipulated negative futures were close, defensive pessimists felt bad and performed well; results suggested that viewing negative futures as close may be part of their natural strategy. Study 3 found that prospective self-appraisals influenced performances through felt preparation. Optimists did not use prospective self-appraisals (Study 1) and their performances were unaffected by manipulated temporal distance (Studies 2 and 3). Discussion centers on prospective self-appraisals and multiple strategies of defensive pessimists.  相似文献   
84.
Early locomotor behavior has been the focus of considerable attention by developmentalists over several decades. Few studies have addressed explicitly patterns of muscle activity that underlie this coordination pattern. Our purposes were to illustrate a method to determine objectively the onset and offset of muscle firings during early walking and to investigate the emergence of patterns of activation of the core locomotor muscles. We tested eight toddlers as they walked overground at walking onset (max. of 3-6 independent steps) and after three months of walking experience. Surface electrodes monitored activity of the gastrocnemius, tibialis anterior, quadriceps, and hamstrings. We reduced EMG signals to a frame-by-frame designation of "on-off," followed by muscle state and co-contraction analyses, and probability distributions for each muscle's activity across multiple cycles. Our results clearly show that at walking onset muscle activity was highly variable with few, if any, muscles showing recurring patterns of behavior, within or among toddlers. Variability and co-activation decreased with walking experience but remained inconsistent, in contrast to the significant increase in stability shown for joint coordination and endpoint (foot placement) parameters. We propose this trend emerges because of the high number of options (muscle combinations) available. Toddlers learn first to marshal sufficient force to balance and make forward progress but slowly discover how to optimize these resources.  相似文献   
85.
This paper considers a family of inductive problems where reasoners must identify familiar categories or features on the basis of limited information. Problems of this kind are encountered, for example, when word learners acquire novel labels for pre-existing concepts. We develop a probabilistic model of identification and evaluate it in three experiments. Our first two experiments explore problems where a single category or feature must be identified, and our third experiment explores cases where participants must combine several pieces of information in order to simultaneously identify a category and a feature. Humans readily solve all of these problems, and we show that our model accounts for human inferences better than several alternative approaches.  相似文献   
86.
The current study applies semantic differential to explore the semantic perception of emergency signs, in an attempt to analyze the meanings of emergency signs in regard to the psychological exigencies of the general public. The results indicate that problems concerning recognition accuracy have been observed, but also that the evaluation of the semantic meaning of the signs is positive. However, a number of emotional factors also emerge, indicating that if improvements should be made to the existing emergency signs, it would better facilitate evacuation in the event of an emergency. As for the design guidelines, the emergency signs should be readily recognizable and have a single meaning. Multiple symbolic meanings should be eliminated. Concrete design guidelines include: (a) safety movement, (b) clarity, and (c) safety. To avoid confusion in sign recognition, in addition to the improvements made based on the abovementioned guidelines, educational promotional activities carried out by the government would also prove very beneficial.  相似文献   
87.
An enhancement of the UV-visible optical absorption spectra of Ag nanoparticles (NPs) deposited on indium tin oxide (ITO) surfaces of different resistance by a seed-mediated growth technique is presented. A bicolour coherent beam, obtained from a pulsed Nd:YAG laser providing a 1060-nm fundamental wavelength and a double-frequency one at 530?nm, was used. A significant change in the optical density is observed for Ag NPs on low-resistance ITO surfaces (≈4?Ω/square), while almost nothing occurs with high-resistance (≈50?Ω/square surfaces). The spectral position of the maximal absorption at 440?nm is almost preserved in both cases. This result is explained in terms of a local photoinduced static field and surface-plasmon polaritons interacting with photoexcited phonons. A grating effect, arising from the coherent bicolour light forming a superstructure as for quantum crystals, could be another contribution.  相似文献   
88.
知情同意作为生命伦理的重要原则,在基因研究中同样占据重要的地位,由于基因研究中知情同意的异质性,在基因研究中面临着诸如如何理解其知情同意的异质性、群体知情同意、基因知情与基因隐私、利益冲突等问题.通过分析基因研究中知情同意的特殊性,综合国内外此领域的已有研究,运用理论联系实际的方法,得出结论认为,只有正确区分基因知情与基因隐私的权利主体,用伦理规范来解决利益冲突,在发展中不断完善知情同意,才能够取得科技与伦理的共赢.  相似文献   
89.
90.
Past research has attempted to delineate personality differences between insomniacs and good sleepers but has failed to control for type of insomnia or severity of the disorder. The purpose of this study was to compare MMPI scores of mild and severe sleep onset insomniacs with a control group of noninsomniacs. Results demonstrated that sleep onset insomniacs, regardless of degree of severity, differed significantly from noninsomniacs; and that mild and severe insomniacs differed from each other on only one MMPI scale.  相似文献   
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