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551.
In the present study we assess a new model for classical conditioning of odor preference learning in rat pups. In preference learning beta(1)-adrenoceptors activated by the locus coeruleus mediate the unconditioned stimulus, whereas olfactory nerve input mediates the conditioned stimulus, odor. Serotonin (5-HT) depletion prevents odor learning, with 5-HT(2A/2C) agonists correcting the deficit. Our new model proposes that the interaction of noradrenergic and serotonergic input with odor occurs in the mitral cells of the olfactory bulb through activation of cyclic adenosine monophosphate (cAMP). Here, using selective antibodies and immunofluorescence examined with confocal microscopy, we demonstrate that beta(1)-adrenoceptors and 5-HT(2A) receptors colocalize primarily on mitral cells. Using a cAMP assay and cAMP immunocytochemistry, we find that beta-adrenoceptor activation by isoproterenol, at learning-effective and higher doses, significantly increases bulbar cAMP, as does stroking. As predicted by our model, the cAMP increases are localized to mitral cells. 5-HT depletion of the olfactory bulb does not affect basal levels of cAMP but prevents isoproterenol-induced cAMP elevation. These results support the model. We suggest the mitral-cell cAMP cascade converges with a Ca(2+) pathway activated by odor to recruit CREB phosphorylation and memory-associated changes in the olfactory bulb. The dose-related increase in cAMP with isoproterenol implies a critical cAMP window because the highest dose of isoproterenol does not produce learning.  相似文献   
552.
This study examined the age and content of earliest childhood memories of self and others. European American and Taiwanese participants (N= 111) retrieved their earliest memories in response to the cue words self, mother, family, friend, and surroundings. Memory for mother was from an earlier age than memory for self, and memories for mother, family, and friend were more socially oriented in content than memories for self or surroundings. In addition, in response to all cue words, Euro-Americans recalled memories from an earlier age than did Taiwanese. Euro-Americans also had a greater tendency to report memories of specific events and focused more on their own roles and autonomy than did Taiwanese, who more often described routine events and emphasized the roles of others. These findings have important implications for infantile amnesia and the memory-self interplay.  相似文献   
553.
554.
In this paper, we study corporate social responsibility (CSR) in China through the prism of investments. We work with large stocks and assess their CSR performance from agency CSR data. We formulate Chinese CSR by a multiple objective extension of a traditional portfolio selection model and analytically solve the extension. We also solve the extension by a genetic algorithm and directly evaluate the algorithm's performance against the analytical solution. The multiple objective formulation is tested by randomly choosing nondominated portfolios with out‐of‐sample data to identify nondominated portfolios that outperform the 1/n portfolio (equally weighted portfolio). Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
555.
随着以用户间交互为特征的Web 2.0理念的深入发展,顾客期望借助互联网参与到价值的生产与创造过程中,以期通过自我潜能发挥和自我价值展示寻求获得一种有别于享乐型快乐感的实现型快乐感.以往顾客参与研究大多关注其经济利益、如何管理、影响因素、获得的实际利益,而对于顾客参与过程中的心理机制和参与后的心理收获研究不多.本研究以互联网为背景,从顾客视角出发,科学采用实验、实证等多种方法,并尝试采用生理仪器(如多导仪、脑电核磁共振仪等)采集顾客行为和生理的客观数据,利用自我决定理论对顾客参与过程的心理反应和参与后的心理收获进行系统探讨,构建顾客参与过程的心理动态模型.  相似文献   
556.
修订Martin等人编制的认知灵活性问卷并对我国大学生的认知灵活性进行测量。首先对366名大学生预测;然后对300名大学生正式测试;并对240名大学生进行效标效度研究;另外对785名大学生初步使用该问卷。结果表明:(1)中文修订版大学生认知灵活性问卷的项目区分度、Cronbachα系数、重测信度、结构效度和效标效度等心理测量学指标良好,可作为我国大学生认知灵活性的研究工具。(2)有社会实践经验大学生的认知灵活性显著高于无社会实践经验大学生;文科女生的认知灵活性显著高于理科女生。  相似文献   
557.
Two experiments were conducted to explore culture and self-priming effects on memories of Caucasian and Asian American adults (N = 526). In the experimental conditions, either the collective or private self was primed prior to retrieval. Participants then described their earliest childhood memories (Study 1) or recalled a fictional story (Study 2). Systematic cultural differences in memory content were obtained across both memory tasks, independent of priming conditions. Caucasians tended to recall specific, one-moment-in-time events that focused on the individual as the central character. Asians tended to provide memories of general, routine events centring on collective activities and social interactions. Priming effects also emerged: memory content reflected the particular aspect of the self being primed. Findings are discussed in light of the interactive relation between memory representations and memory narratives and the role culture plays in remembering.  相似文献   
558.
People tend to hold an optimistic view of their futures. Using a novel paradigm to examine the anticipated change from the personal past to the personal future, we found that the future was not always perceived as brighter than the past. College students (N = 156) recalled positive and negative personal events of various situations. Following each recall, they imagined a future personal event involving the same situation. Participants expected over half of the events to change in either upward or downward directions, depending on the valence of the past events. In addition, participants anticipated greater changes in domains of less stability, and Asians anticipated greater changes than European Americans. Anticipated future changes were further associated with psychological well-being. The findings shed new light on future event simulation.  相似文献   
559.
ABSTRACT

A comparative study of the effect of two different welding wires (W2 and Thermanit MTS-616 welding wire W1) on T92 welded joints has been made. Both wires showed good weldability and no defects in the welds were found. The hardness of the welded joint using W2 wire was lower than using W1. The toughness and high temperature (600°C) strength of the weld using W2 wire were higher than those using W1. The two welding wires produce joints having little difference in plasticity at room and high temperature. Large pores in both joints are related to the second phase of the larger particles in the matrix. The second phase of particles in the matrix easily caused cracks, which is unfavourable for the improvement of plasticity. Precipitation of the second phase of large particles in the matrix should be minimised for optimised welds.  相似文献   
560.
The present study examined the influence of trait Agreeableness and its interaction with social role status on interpersonal correspondence as reflected in the within‐person relation between a person's communal (agreeable‐quarrelsome) behavior and perceptions of the interaction partner's communal behavior. We used a sample of working adults (original data set: 113 participants and 12,303 interpersonal events; constrained data set in the work setting: 109 participants and 3,193 interpersonal events) and an event‐contingent recording procedure to assess behavior in naturalistic interpersonal events. The results of multilevel modeling indicated that interpersonal correspondence was lower for high trait Agreeableness persons than for low trait Agreeableness persons, apparently due to less responsiveness to more disagreeable behavior by the other person in an interaction. High Agreeableness persons manifest greater interpersonal correspondence when in a high‐status role than when in a low‐status role, apparently by increasing responsiveness to disagreeable behavior from others. The results imply that high social role status may influence the effortful control process of high trait Agreeableness persons over their behavioral reactions to others' disagreeable behavior during interpersonal interactions.  相似文献   
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