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51.
The application of a high magnetic field is capable of inducing the formation of aligned equiaxed grains in alloys during directional solidification. The alignment and refinement of the grains is enhanced as the magnetic field intensity increases. The thermoelectric power difference at the liquid/solid interface in four alloys has been measured in situ during directional solidification and it is concluded that the formation of aligned equiaxed grains in a magnetic field should be attributed to the combined action of a thermoelectric magnetic force and a magnetization force.  相似文献   
52.
Previous studies on visual working memory (VWM) have primarily investigated memory for an array presented for a single moment. Here, we examined VWM for two arrays separated by a 1,100-msec interval. We focused on the allocation of VWM capacity to the two arrays as a function of dynamic events inserted between them. During the interval, irrelevant dots moved to form three types of motion: (1) coherent (apparent) motion that connected Arrays 1 and 2, (2) jumpy motion, or (3) coherent motion with two disconnected segments. Results showed that VWM for Array 2’s locations was better than for Array 1’s, especially when the arrays were connected by coherent motion. We suggest that coherent motion between two temporally disparate arrays connects the arrays into a single visual event VWM is then biased toward remembering the more recent state of the event.  相似文献   
53.
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   
54.
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   
55.
The present research investigated whether certain conceptualizations of time influence the planning fallacy or the tendency to underestimate predicted task durations. In Experiment 1, participants were presented with one of three types of primes (video, linguistic, video + linguistic) that reflected either an ego or time motion perspective (i.e. an individual moving through time vs. time moving toward an individual). Afterwards, all participants predicted the amount of time required to sort and shelve a stack of journals before actually completing the task. The results showed that across all priming conditions, subjects in the ego motion condition underestimated to a greater extent than those in the time motion condition. Experiment 2 replicated this effect and also found that underestimations are reduced when the implied duration of the experimental session is short vs. long. As a set, these findings have relevant theoretical implications and suggest some potential de-biasing techniques.  相似文献   
56.
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   
57.
患者知情同意权代理行使是医疗实践中普遍存在的问题。我国相关法律存在规定原则性过强、与患者自主决定权之间存在矛盾以及对侵犯患者利益的救济途径不明确等不足。应从确立患者利益最大化原则、将知情同意权代理行使的相关规定具体化以及适度运用紧急避险原则等几方面完善我国的患者知情同意权代理行使制度。  相似文献   
58.
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   
59.
宗教认知科学是新近出现的从认知和进化的角度研究宗教的分支学科。主要有认知副产物和社会适应两种理论。认知副产物理论认为宗教信仰是人类认知倾向的副产物;社会适应理论认为宗教信仰促进群体的团结合作,是一个精巧的社会适应机制,有助于群体的自然选择。两种理论引发了系列的实验研究,由于宗教认知科学仍处于理论研究向实证研究的过渡阶段,未来需统一概念,加强实验范式的建立,更多地借助认知科学的方法和工具开展实证研究。  相似文献   
60.
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   
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