Galpha(i2) inhibition of adenylate cyclase regulates presynaptic activity and unmasks cGMP-dependent long-term depression at Schaffer collateral-CA1 hippocampal synapses

Cyclic AMP signaling plays a central role in regulating activity at a number of synapses in the brain. We showed previously that pairing activation of receptors that inhibit adenylate cyclase (AC) and reduce the concentration of cyclic AMP, with elevation of the concentration of cyclic GMP is sufficient to elicit a presynaptically expressed form of LTD at Schaffer collateral-CA1 synapses in the hippocampus. To directly test the role of AC inhibition and G-protein signaling in LTD at these synapses, we utilized transgenic mice that express a mutant, constitutively active inhibitory G protein, Galpha(i2), in principal neurons of the forebrain. Transgene expression of Galpha(i2) markedly enhanced LTD and impaired late-phase LTP at Schaffer collateral synapses, with no associated differences in input/output relations, paired-pulse facilitation, or NMDA receptor-gated conductances. When paired with application of a type V phosphodiesterase inhibitor to elevate the concentration of intracellular cyclic GMP, constitutively active Galpha(i2) expression converted the transient depression normally caused by this treatment to an LTD that persisted after the drug was washed out. Moreover, this effect could be mimicked in control slices by pairing type V phosphodiesterase inhibitor application with application of a PKA inhibitor. Electrophysiological recordings of spontaneous excitatory postsynaptic currents and two-photon visualization of vesicular release using FM1-43 revealed that constitutively active Galpha(i2) tonically reduced basal release probability from the rapidly recycling vesicle pool of Schaffer collateral terminals. Our findings support the hypothesis that inhibitory G-protein signaling acts presynaptically to regulate release, and, when paired with elevations in the concentration of cyclic GMP, converts a transient cyclic GMP-induced depression into a long-lasting decrease in release.     

内疚和羞耻的关系——来自反事实思维的验证

运用情境模拟法从反事实思维的角度探讨内疚与羞耻的关系.并比较了大学生和青少年罪犯反事实思维与内疚和羞耻关系方面的特点.结果表明:(1)研究结果部分支持"内疚事件和羞耻事件"假设,但不支持Lewis提出的"自我和行为"假设,甚至与该假设相反;(2)大学生和青少年罪犯反事实思维与内疚和羞耻的关系具有某些方面的一致性.但也存在着很大的差异.大学生自我导向的反事实思维与内疚感有更为密切的联系,而青少年罪犯行为导向的反事实思维与羞耻感有更为密切的联系.     

双重攻击模型的实证研究

本研究通过两个实验对双重攻击模型进行了验证.实验一借助实验性分离的逻辑,发现性别对内隐攻击性和外显攻击性存在不同影响,初步证明内隐攻击性和外显攻击性的分离论.实验二通过实证性因素分析,证明双重攻击模型具有较高的拟合参数.本研究证明内隐攻击性和外显攻击性分属两个不同的结构,构成双重攻击模型.     

周代战车驾马数探析

两周时期是车战盛行的时代,从上古文献记载来看,几乎是整齐划一的驷马驾车格局。然而仔细梳理两周时期的考古发现可见,文献记载与考古发现不相吻合,而地下出土文献如金文、简帛文献可以与考古实物相互印证,即以二马之驾居多。这说明,战车驾二是当时的驾马常制,传世文献多文学作品,有溢美之处。     

Existential function of babies: Babies as a buffer of death-related anxiety

The present study examined babies as death anxiety buffers with Chinese participants in three experiments. In Experiment 1, death-related thoughts increased college-aged participants' interest in human babies. In Experiment 2, images of newborn animals reduced the number of death-related thoughts recorded by college-aged participants. In Experiment 3, female factory workers who read news articles describing deaths of babies had pessimistic estimations of their own life expectancies. An explanation of these results is provided within a terror management theory framework, with a primary focus on how babies reinforce cultural worldviews and enhance self-esteem via the notion of symbolic immortality. Thus, the anxiety-buffering function of baby is subsumed under cultural worldviews validation and self-esteem enhancement.     

汉语词汇习得的年龄效应：语义假设的证据

通过三个实验考察了词汇加工中的习得年龄效应。实验一对比了汉字命名和图片命名中词汇习得的年龄效应,发现图片命名中存在着较大的词汇习得的年龄效应,汉字命名中没有出现这种效应。实验二和实验三分别采用语义范畴判断任务和图片语义分类任务,两个实验均发现了词汇习得的年龄效应。实验结果说明,词汇习得的年龄效应至少部分来源于语义加工的层次,结果支持了语义假设的观点     

一份面向青年的基督教刊物——《青年问题》

本文在研读大量原始资料的基础上,对卫理公会华西教区在成都办的《青年问题》月刊做了全面分析,内容包括该刊的创办历史、组织机构、内容特色与经营管理,并对其历史价值做了实事求是的评价。     

Chinese kindergartners’ automatic processing of numerical magnitude in Stroop-like tasks

Using Stroop-like tasks, this study examined whether Chinese kindergartners showed automatic processing of numerical magnitude. A total of 36 children (mean age 5 5 years 10 months) were asked to perform physical size comparison (i.e., “Which of two numbers is bigger in physical size?”) and numerical magnitude tasks (i.e., “Which of two numbers is bigger in numerical magnitude?”) on 216 number pairs. These number pairs varied in levels of congruence between numerical magnitude and physical size (for Stroop effect) and numerical distance (for distance effect). On the basis of analyses of response time and error rates, we found that Chinese kindergartners showed automatic processing of numerical magnitude. These results are significantly different from previous studies’ findings about the onset age (ranging from around the end of first grade to third grade) for automatic processing of numerical magnitude.     

When is educational specialization heterogeneity related to creativity in research and development teams? Transformational leadership as a moderator

The authors examined conditions under which teams' educational specialization heterogeneity was positively related to team creativity. Using a sample of 75 research and development teams, the authors theorized and found that transformational leadership and educational specialization heterogeneity interacted to affect team creativity in such a way that when transformational leadership was high, teams with greater educational specialization heterogeneity exhibited greater team creativity. In addition, teams' creative efficacy mediated this moderated relationship among educational specialization heterogeneity, transformational leadership, and team creativity. The authors discuss the implications of these results for research and practice.     

If it goes up, must it come down? Chronic stress and the hypothalamic-pituitary-adrenocortical axis in humans

The notion that chronic stress fosters disease by activating the hypothalamic-pituitary-adrenocortical (HPA) axis is featured prominently in many theories. The research linking chronic stress and HPA function is contradictory, however, with some studies reporting increased activation, and others reporting the opposite. This meta-analysis showed that much of the variability is attributable to stressor and person features. Timing is an especially critical element, as hormonal activity is elevated at stressor onset but reduces as time passes. Stressors that threaten physical integrity, involve trauma, and are uncontrollable elicit a high, flat diurnal profile of cortisol secretion. Finally, HPA activity is shaped by a person's response to the situation; it increases with subjective distress but is lower in persons with posttraumatic stress disorder.