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201.
Receiving favors is often a mixed blessing and commonly triggers two emotions: the positive emotion gratitude and negative emotion indebtedness. In three studies, we examined the hypothesis that gratitude and indebtedness have distinct functions in social exchange. Contrary to current views, we believe that the function of gratitude does not primarily reside in facilitating social exchange. Instead, we propose that indebtedness motivates people to repay favours received, and thus accounts for most of the prosocial effects commonly attributed to gratitude. On the other hand consistent with current views, we believe that gratitude signals the potential for developing a relationship and fosters proximity seeking. Supporting these assumptions, in Study 1 we found that gratitude and indebtedness were associated with aspects of the favour that reflect the concern for relationship and the level of inequity. Studies 2 and 3 provided causal support for these relations, and revealed the unique associations between gratitude and the motivation of proximity seeking, and between indebtedness and the motivation to reciprocate. We argue that this functional distinction has escaped research attention as gratitude and indebtedness are naturally correlated because they stem from the same eliciting event. To appreciate this functional distinction, both emotions should be studied simultaneously in the context of social exchange.  相似文献   
202.
The episodic effect suggests that episodic prospection (imagining future events) can effectively reduce time discounting, the propensity to discount the value of delayed rewards relative to immediate ones. However, less clear is how episodic prospection modulates time preference. As engagement in episodic prospection usually evokes prospective emotions, it was proposed that episodic prospection might work by inducing prospective emotions. Although one previous study has attempted to provide evidence to the emotional account of the episodic effect, shortcomings in its experimental design make its conclusion questionable. In this study, we replicated previous experimental design with improvements to further test the effects of prospective emotion on time preference. By manipulating the emotional valency associated with episodic prospection in a delay discounting task, we found that positive episodic prospection attenuated time discounting; negative episodic prospection exacerbated time discounting; and episodic prospection did not shift time preference when prospective emotion is removed. These results were essentially identical to the result of the previous study. Together, these studies suggested that the effects of episodic prospection depended on prospective emotion. Thus, one cannot ignore prospective emotion if counting on episodic prospection to combat humans’ impulsive behaviours.  相似文献   
203.
智力运动是以开发智力为目的且涉及到较多认知活动的竞技运动。研究表明, 长期的智力运动经验会影响专家在领域内任务中知觉及记忆的行为表现及其大脑活动。智力运动经验使专家知觉广度增大的同时, 促进专家对棋子关系进行整体性知觉加工, 且这一过程与颞顶联合区、缘上回、压后皮质、侧副沟、梭状回等区域有关; 在长时记忆中存储的具体(空间位置)及抽象信息(知识、策略、棋子关系等)是专家记忆优势发生的基础, 该过程与内侧颞叶、额叶和顶叶有关。未来研究可以从智力运动类型、创新实验范式, 结合测量设备及认知特点, 深入探讨智力运动专家整体知觉优势及记忆优势的神经机制, 为人工智能和技能训练等提供理论依据。  相似文献   
204.
205.
The present study investigated whether the neural correlates for auditory feedback control of vocal pitch can be shaped by tone language experience. Event-related potentials (P2/N1) were recorded from adult native speakers of Mandarin and Cantonese who heard their voice auditory feedback shifted in pitch by −50, −100, −200, or −500 cents when they sustained the vowel sound /u/. Cantonese speakers produced larger P2 amplitudes to −200 or −500 cents stimuli than Mandarin speakers, but this language effect failed to reach significance in the case of −50 or −100 cents. Moreover, Mandarin speakers produced shorter N1 latencies over the left hemisphere than the right hemisphere, whereas Cantonese speakers did not. These findings demonstrate that neural processing of auditory pitch feedback in vocal motor control is subject to language-dependent neural plasticity, suggesting that cortical mechanisms of auditory-vocal integration can be shaped by tone language experience.  相似文献   
206.
为探讨平板运动试验(treadmill exercise testing,TET)心脏变时功能不套(chronotropic incompetence,CI)对冠心病(coronary heart disease,CHD)的诊断价值,分析112例临床拟诊冠心病患者,先后均行TET及冠状动脉造影检查(coronary angiography,CAG),并按CAG结果分为CHD组和非CHD组,分析比较两组间心脏变时性指标;并对传统的ST标准、CI指标及两项指标联合诊断冠心病的敏感性、特异性、准确性进行比较.运动后最大心率小于预测最大心率的85%和变时性指数(chronotropic response index,CRI)小于0.8为心脏变时功能不全.结果表明CHD组运动后最大心率、CRI两种变时功能不全的指标均低于非CHD组(P<0.01);与传统的ST段标准相比,CI指标诊断CHD的敏感性、特异性、准确性无明显差异(P>0.05),而两项指标联合诊断冠心病的敏感性与传统的ST段标准相近,特异性及准确性显著高于传统ST标准,差异有统计学意义(P<0.05).故CI指标是诊断CHD的重要价值的指标,可以提高TET对CHD的诊断率.  相似文献   
207.
In spite of many superior high-temperature properties of intermetallics, it has been difficult to understand their intrinsic brittleness. To eliminate or improve the embrittlement, the conventional alloying technique based on the trial-and-error method is still the most effective and practical. However, it remains a main challenge for both physicists and materials scientists to provide either an alloying principle or a deep insight into its toughening mechanism at an atomic or electronic level. This letter reports a simple experimental approach that uses work function (WF) as a sensitive indicator of the role of alloying in changing mechanical behavior. NiAl is chosen as a typical example. It is found that with the addition of Cr and Ce, the ductility of NiAl increases significantly. Such an increase in ductility corresponds to a concomitant decrease in the WF, which is attributed to a change in the nature of the atomic bonding or in the electronic structure induced by the alloying. This fundamental understanding on the embrittlement nature of NiAl could provide some alloying guidelines or principles for other intermetallics.  相似文献   
208.
This study employed Ecological Momentary Assessment to test predictions from appraisal theories of emotion about the relationships between emotions and appraisals, using a sample of police officers from Singapore. Strong support was obtained for the predictions, thus demonstrating ecological validity of appraisal theories while circumventing shortcomings of previously used methods in appraisal studies. The results also indicate that the emotions were accounted for by specific configurations of appraisals over and above those accounted for by individual constituent appraisals.  相似文献   
209.
The aim of this study was to investigate the use of a newly developed design game called BLOCKS to stimulate awareness of ethical responsibilities amongst engineering students. The design game was played by seventeen teams of chemical engineering students, with each team having to arrange pieces of colored paper to produce two letters each. Before the end of the game, additional constraints were introduced to the teams such that they faced similar ambiguity in the technical facts that the engineers involved in the Challenger disaster had faced prior to the space shuttle launch. At this stage, the teams had to decide whether to continue with their original design or to develop alternative solutions. After the teams had made their decisions, a video of the Challenger explosion was shown followed by a post-game discussion. The students’ opinion on five Statements on ethics was tracked via a Five-Item Likert survey which was administered three times, before and after the ethical scenario was introduced, and after the video and post-game discussion. The results from this study indicated that the combination of the game and the real-life incident from the video had generally strengthened the students’ opinions of the Statements.  相似文献   
210.
小细胞肺癌(small cell lung cancer,SCLC)生长迅速,具有高度的侵袭性,就诊时多数患者已发生远处转移,对于广泛期小细胞肺癌,治疗仍以全身化疗为主,在过去30余年里,EP/CE方案作为标准一线化疗方案在治疗广泛期小细胞肺癌中取得了较高的缓解率,但多数患者在化疗停止6个月内疾病发生进展,2年的生存率不足5%,我们需要更加积极有效的一线化疗方案,本文综述了近10余年来广泛期小细胞肺癌的一线化疗进展.  相似文献   
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