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1. chinaXiv:202006.00200 [pdf]

关于手性问题的讨论.pdf

史志强
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

本文是对《中国科学》一个编者按的商榷和讨论。文章指出手性是手性对称性的破缺,并举例说明了手性对称性和手性的本质区别。手性化合物的一对对映体有不同的生物活性和药物活性,这决不是个别极端的例子,而是非常普遍存在的。生物体内参与蛋白质组成的氨基酸是手性的,但它们既不全都是左旋的,也不全都是右旋的,只能说它们全部都是L构型的。蛋白质的结构是复杂的,我们不能笼统地说蛋白质是右旋的,只能说蛋白质二级结构中的α-螺旋结构是右旋的。最后,我们分析了对手性定义的几种错误表述,并指出产生这些错误的原因。

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2. chinaXiv:202006.00172 [pdf]

Reconfiguration of functional brain networks underlying the distinctions between automatic and controlled handwriting

Junjun LI; Lei HONG; Hong-yang BI; Yang YANG
Subjects: Psychology >> Cognitive Psychology

This study aimed to examine the brain mechanisms underlying the distinctions between automatic and controlled handwriting. Functional magnetic resonance imaging data were collected while adult participants (n = 53) performed a copying task with varying speed control demands. Network analysis showed significant differences in functional connectivity within and between the frontoparietal network (FPN), the default mode network (DMN), the dorsal attention network (DAN), the somatomotor network (SMN) and the visual network (VN) between automatic and speed-controlled handwriting irrespective of written materials, which are thought to reflect general executive control and task-relevant visuomotor operations. However, there were no differences in brain activation between automatic and controlled handwriting. These results suggest that reconfiguration of functional network architecture, rather than regional activation, underlies the dissociations between automatic and controlled handwriting. Our findings shed new light on the neural mechanisms of handwriting mastery and handwriting impairments in individuals with neurological disorders.

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3. chinaXiv:202006.00171 [pdf]

隔代教育对孙辈和祖辈的影响:双刃剑效应

卢富荣; 宋煜静; 刘路培; 方选智; 张彩
Subjects: Psychology >> Developmental Psychology

隔代教育是指祖辈对孙辈的抚养和教育,随着经济社会的发展,“隔代教育”已成为“亲代教育”的一种重要补充形式。隔代教育对祖孙两辈人的身心健康均存在“双刃剑”效应。生物进化论、社会交换理论和家庭系统理论为理解隔代教育对孙辈的影响提供了理论支持,角色紧张和角色强化理论可以加深隔代教育对祖辈影响的认识。未来研究应明确隔代教育的定义和类型,控制边界因素进行更为深入的综合性研究,并进一步推进隔代教育的本土化研究。

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