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青少年时期是一个转折期,也是冒险行为多发的时期。以往有关青少年冒险行为的研究大多集中在心理学视角与社会关系学视角,双系统竞争理论从生物学视角对青少年高冒险行为作出解释。该理论认为青少年高冒险行为的产生主要是由于大脑中的社会情绪系统与认知控制系统相互竞争作用的结果。社会情绪系统对奖赏寻求起作用,而认知控制系统对执行功能起作用。较早发展的社会情绪系统与较晚才成熟的认知控制系统间的竞争是青少年冒险行为产生的原因。 相似文献
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Ya‐Ling Wang Yi‐Cheng Lin Chin‐Lan Huang Kuang‐Hui Yeh 《Asian Journal of Social Psychology》2012,15(3):198-207
Psychological distance in terms of its purpose as a psychological adjustment is currently not well understood. Some researchers claim that psychological distance serves as an emotion regulator, while others argue that psychological distance has the reverse effect, leading to cognitive avoidance and rumination. To elucidate upon this discrepancy, we propose that a complementary matching of psychological distance to one's habitual psychological distance perspective may lead to better emotion regulation when compared to the original perspective (i.e. fixing on either psychological immersion or distance). This study hypothesizes that a complementary matching of psychological distance to one's habitual perspective generally leads to better emotion regulation; specifically, individuals with high avoidant attachment, who habitually distance themselves from their experiences, may benefit from psychological immersion, while individuals with high anxious attachment, who habitually immerse themselves in their experiences, may benefit from psychological distancing. A total of 83 participants completed measures of adult attachment orientations; read a conflict scenario, triggering their attachment systems; and then rewrote that scenario using designated pronouns, thereby employing psychological immersion or psychological distance. Participants in the self‐immersed condition were asked to write from the first‐person perspective, whereas those in the self‐distancing condition were asked to write from the third‐person perspective. The results support our hypothesis of a complementary matching of psychological distance and habitual perspective. 相似文献
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用SDQ(家长版)对上海10所小学二至四年级学生进行测查,以探求被试的ADHD症状表现,锁定ADHD高风险儿童。结果:(1)男生ADHD得分偏高(p<.01),但女生在红橙两个级别内的百分数均高于男生;(2)9岁被试的ADHD得分分布最分散,占男生ADHD红色级别的比例最大,在女生ADHD得分中均值最大;(3)红橙两个级别为高风险级别。结论:(1)9岁是ADHD症状表现最严重的年龄;(2)女生具有更高的ADHD风险;(3)ADHD高风险被试晒出率:男生14.4%,女生17.4%。 相似文献
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A numerical calculation method based on the angle in a triple junction composed of a random grain boundary is proposed to predict the connectivity and stability of a grain boundary in a B10 copper-nickel alloy. The grain-boundary connectivity and its effect on corrosion resistance are studied combining computer-aided analysis with electrochemical impedance testing. The results show that the prediction of corrosion resistance using a grain-boundary connectivity numerical method is consistent with immersion experimental results. The B10 alloy exhibited the best corrosion resistance after cold rolling with a 9% reduction rate. The relationship between the grain-boundary characteristics and corrosion resistance is well established using the numerical method to quantify the grain-boundary connectivity. A higher connective frequency and a low proportion of grain-boundary angles between 60° and 180° in the triple junction is detrimental to corrosion resistance of the B10 alloy. 相似文献
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S. J. Zhou 《Philosophical Magazine Letters》2013,93(10):773-784
The elastic displacement field of a jogged screw dislocation is obtained analytically from Burgers equation. With this analytic solution, a pair of jogs in a screw dislocation is implemented into molecular-dynamics simulations. The dislocation line bows out between two jog pinning points and breaks away when the line tension of the dislocation exceeds a certain critical value. The creation of vacancies and interstitials is observed during the non-conservative motion of the jogged screw dislocation in γ-TiAl. The structures of vacancies and interstitials are discussed. 相似文献
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BiFe1? x Ta x O3 (x = 0, 0.05, 0.1) nanopowders have been fabricated by a simple sol–gel method. Dielectric measurements at microwave frequencies (2–18 GHz) were made using a vector network analyser. Without tantalum, the BiFeO3 nanopowder presents a relaxation-like response with a characteristic frequency of 15 GHz, which can be associated with an overdamped process. The Ta-doped nanopowders, however, show resonant behaviour with resonant frequencies of 12.5 and 14.6 GHz. The intensity of the resonant peak near 14.6 GHz decreases with increasing Ta addition. This behaviour is associated with a damped resonance process. Room-temperature magnetic measurements indicate that the addition of Ta influences the magnetic properties of the BiFeO3 nanopowders, with BiFe0.95Ta0.05O3 having the strongest ferromagnetism with a saturation magnetisation M s of about 0.05 µB/Fe. The origin of the enhanced ferromagnetism is possibly associated with the distortion of the oxygen octahedral by the Ta substitution or/and the statistical distribution of Fe3+ and Fe2+. 相似文献