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81.
82.
Yang H  Jin G  Ren D  Luo S  Zhou T 《Brain and cognition》2011,76(1):206-210
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.  相似文献   
83.
本研究通过初始问卷编制、项目分析、探索性因素分析和验证性因素分析等程序,编制普通高校大学生综合国防素质量表,并进行了相关实证测量。结果显示,量表有8个维度共35个题项。量表的α系数和重测信度均符合心理测量学指标要求,具有良好的结构效度、聚敛区分效度与校标关联效度,可用于大学生综合国防素质的测量。测量结果发现,大学生综合国防素质总体处于中等偏上水平,且存在显著的性别差异与年级差异。  相似文献   
84.
以146名小学一年级儿童为研究对象, 进行了历时2年的3次追踪测试, 考察小学生从一到三年级的语素意识、汉字识别和词汇知识之间发展关系的变化。在控制了语音意识、快速命名、正字法意识、一般认知能力和自回归效应后, 结果发现:(1)一年级时的汉字识别显著预测二年级的同音语素意识和同形语素意识; (2)一年级时的词汇知识显著预测二年级的复合语素意识和汉字识别; (3)二年级时的汉字识别和词汇知识对三年级的同音语素意识、同形语素意识和复合语素意识均有显著预测作用; (4)二年级时的同形语素意识对三年级的词汇知识具有显著预测作用。结果表明, 小学一至三年级的汉字识别和词汇知识对语素意识具有预测作用; 三种语素意识对汉字识别和词汇知识的预测作用中, 只有同形语素意识能够显著预测词汇知识; 三种语素意识、汉字识别和词汇知识的发展关系存在变化且具有阶段性特点。  相似文献   
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86.

Goal complexes, which are formed by pairing standards of competence strivings with their underlying reasons, are essential to an understanding of achievement goal regulation. This paper examines goal complexes that cross other-approach and other-avoidance goals with the approach-avoidance dimensions of Big Three motives as underlying reasons. 220 undergraduates participated in Study 1 which developed and validated the Self-Attributed Motive Scale to measure hope of success, fear of failure, hope of affiliation, fear of rejection, hope of power, and fear of loss of power. Additionally, 235 undergraduates participated in Study 2 where goal complexes were created by crossing the motive items developed in Study 1 with other-approach and other-avoidance goals. The predictive utility of the resultant goal complexes was examined in relation to positive well-being (positive learning-related emotions and engagement), negative well-being (negative learning-related emotions and burnout), and academic buoyancy. The contributions of the studies to the self-attributed motive and goal complex literatures are discussed.

  相似文献   
87.
Weng Hong Tang 《Synthese》2014,191(7):1433-1450
Suppose we wish to provide a naturalistic account of intentionality. Like several other philosophers, we focus on the intentionality of belief, hoping that we may later supplement our account to accommodate other intentional states like desires and fears. Now suppose that we also take partial beliefs or credences seriously. In cashing out our favoured theory of intentionality, we may for the sake of simplicity talk as if belief is merely binary or all-or-nothing. But we should be able to supplement or modify our account to accommodate credences. I shall argue, however, that it is difficult to do so with respect to certain causal or teleological theories of intentionality-in particular, those advanced by the likes of Stalnaker (Inquiry, 1984) and Millikan (J Philos 86:281–297, 1989). I shall first show that such theories are tailor-made to account for the intentionality of binary beliefs. Then I shall argue that it is hard to extend or supplement such theories to accommodate credences. Finally, I shall offer some natural ways of modifying the theories that involve an appeal to objective probabilities. But unfortunately, such modifications face problems.  相似文献   
88.
Research has indicated that highly trait-anxious (HTA) individuals exhibit a specific deficit in filtering threat-related distractors from visual–spatial working memory (WM). Prior demonstrations of impaired inhibition control in HTA individuals have mainly focused on tasks that required the inhibition of prepotent response tendencies. Studies on the suppression of emotionally neutral distractors from WM in trait anxiety have also been minimal. In this article, we present a study on the manifestation of general inefficient filtering of neutral distractors during visual–spatial WM maintenance stages in HTA individuals. Female participants performed a visual–spatial WM task while event-related potentials were recorded. They were made to remember the orientations of red rectangles within half of the screen and to ignore all salient green rectangles. As predicted, no significant main effect of group and no interaction between group and condition were found in the N2pc component, suggesting that group differences did not manifest in the initial process of object individuation. During the subsequent WM maintenance phase, HTA individuals were highly inefficient at filtering the irrelevant items from WM, as reflected not only by parallel late contralateral delay activity (CDA; 450 to 900 ms) amplitudes for the distractor condition and the four red items, but also by a smaller filtering efficiency score in the HTA group than in the low-trait-anxiety group. Extending previous studies, our findings verify a general filtering impairment in HTA individuals for task-irrelevant salient distractors during a WM maintenance phase.  相似文献   
89.
In the aftermath of several school shooting incidents in recent years, students’ perceptions of unsafe schools has been a major concern for parents, teachers, school officials, school practitioners, and policy-makers. Using Bronfenbrenner’s ecological systems framework, we examined the micro-, meso-, and exosystem level factors associated with perceptions of unsafe school environments in a nationally representative sample of 10- to 15-year-old youth in the United States. We found that for the socio-demographic characteristics, students who were older, male, and poor had increased risks of perceiving higher levels of unsafe school environments. Within the microsystem of the family, our results indicate that parent-youth discussions of school activities/events decreased the risk of students perceiving unsafe schools. All of the school environment variables—ease of making friends, teachers’ involvement, observed weapon carrying, and school rule enforcement—were related in the expected direction to students’ perceiving their schools as unsafe. At the mesosystem level, findings from our study demonstrate that variables measuring parental school involvement were unrelated to perceptions of school safety. Finally, at the exosystem level, we found that students’ perceptions of residing in a safer neighborhood and residence in a non-central city metropolitan area, compared with a central city, decreased the odds of perceiving school environments as unsafe. School policy and practice implications are discussed.  相似文献   
90.
This study explored a bidirectional impact on the recognition accuracy of various facial expressions deriving from both the observer and sender in a sample of Chinese participants. A facial manipulation task was used to examine the ability of an observer's facial feedback to modulate the recognition of various facial expressions. Furthermore, the effect of a sender's facial expression with an open or closed mouth on recognition accuracy was investigated. The results showed that only recognition accuracy of a sad facial expression was influenced simultaneously by bidirectional sources from a sender and observer. Moreover, the impact of the unidirectional cue of a sender's facial feature (i.e., mouth openness) on happy and neutral faces was found to influence the recognition accuracy of these faces, but not the observer's bodily state. These findings indicate that the bidirectional impact derived from an observer and sender on facial expression recognition accuracy differs for emotional and neutral expressions.  相似文献   
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