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141.
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
142.
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
143.
Shen YJ Jiang YV 《Journal of experimental psychology. Human perception and performance》2006,32(5):1208-1220
This study investigated memory from interrupted visual searches. Participants conducted a change detection search task on polygons overlaid on scenes. Search was interrupted by various disruptions, including unfilled delay, passive viewing of other scenes, and additional search on new displays. Results showed that performance was unaffected by short intervals of unfilled delay or passive viewing, but it was impaired by additional search tasks. Across delays, memory for the spatial layout of the polygons was retained for future use, but memory for polygon shapes, background scene, and absolute polygon locations was not. The authors suggest that spatial memory aids interrupted visual searches, but the use of this memory is easily disrupted by additional searches. 相似文献
144.
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
145.
Most Chinese characters are composed of a semantic radical on the left and a phonetic radical on the right. The semantic radical provides the semantic information; the phonetic radical provides information concerning the pronunciation of the whole character. The pseudo‐characters in the study consisted of different sub‐lexical parts of real Chinese characters and consequently they also had the semantic radical and the phonetic radical. But they were not readable and had no actual meaning. In order to investigate the spatiotemporal cortical activation patterns underlying the orthographic, phonological and semantic processing of Chinese characters, we used event‐related brain potentials (ERPs) to explore the processing of Chinese characters and pseudo‐characters when 14 healthy Chinese college students viewed the characters passively. Results showed that both Chinese characters and pseudo‐characters elicited an evident negative potential peaking around 120 ms (N120), which appeared to reflect initial orthographic distinction and evaluation. Then, Chinese pseudo‐characters elicited a more positive ERP deflection (P220) than did Chinese characters 200–250 ms after onset of the stimuli. It was similar to the recognition potential (RP) and might reflect the integration processes of phonological and semantic processing on the basis of early orthographic information. Dipole source analysis of the difference wave (pseudo‐characters minus characters) indicated that a generator localized in the left temporal‐occipital junction contributed to this effect, which was possibly related to phonological and perceptual–semantic information integration. Between 350–450 ms, a greater negativity (N360) in pseudo‐characters as compared to characters was found over midline fronto‐central scalp regions. Dipole analysis localized the generator of N360 in the right parahippocampal cortex. Therefore, the N360 might be an N400 component and reflect the higher‐level semantic activation on the basis of orthographic, phonological and perceptual–semantic processing. 相似文献
146.
Chin-Wei Chang Hung-Yi Hsiao Chieh-Hsin Tang Ying-Ji Chuang Ching-Yuan Lin 《Journal of psycholinguistic research》2010,39(1):21-33
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
147.
This essay explores the history of studies in analytical philosophy in China since the beginning of the last century, by dividing
into three phases. It shows that, in these phases, analytic philosophy was always at a disadvantage in confronting serious
challenges coming from both Chinese traditional philosophy and modern philosophical trends. The authors argue that Chinese
philosophers have both done preliminary studies and offered their own analyses of various problems as well as some new applications
of analytic philosophy especially in the latest period. Meanwhile, Chinese traditional philosophy was always trying to adjust
its cultural mentality in the struggle with analytic philosophy, and accommodated in its own way the rationalistic spirit
and scientific method represented in analytic philosophy. 相似文献
148.
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
149.
肥胖是体内脂质过度沉积的一种状态,其不仅可引起糖脂代谢紊乱、胰岛素抵抗,从而继发糖尿病、高血压、冠心病等疾病,而且当脂质水平超过脂肪细胞的储存容量及出现胰岛素抵抗时,血液中游离脂肪酸含量会随之升高,进而可引起脂质在心脏的异位沉积.沉积于心肌细胞的脂质可进一步通过神经酰胺、内质网应激等机制影响心肌细胞的结构和功能,最终导致心力衰竭的发生.但肥胖所致心肌脂毒性具体机制不明,本文就肥胖所致心肌脂毒性可能机制做一综述. 相似文献
150.
The primary purpose of this study was to investigate whether the theory of planned behavior (TPB) mediated the relationship between dialectical thinking and health behaviors. A sample of 285 undergraduates was tested with a dialectical thinking styles scale, health promoting lifestyle profiles, and TPB questionnaires. Structural equation modeling was used for data analysis. Results indicated that all the three dimensions of thinking styles (belief in the connection, acceptance of change, and acceptance of contradiction) exerted significant effects on TPB constructs. Specifically, the connection and the change dimensions had positive effects on health behaviors mediated by TPB, whereas the contradiction dimension had a negative effect. Model 2 showed a satisfactory fit, demonstrating the influential pathways between dialectical thinking and health behaviors. Implications in issues of health promotion and future research are discussed. 相似文献