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101.
高特质焦虑个体常表现出对威胁性刺激的选择性注意偏向的特点。然而其潜在的神经机制目前仍不清楚。通过记录高、低特质焦虑者各17名进行情绪加工时的ERP,比较了两组个体在选择性注意偏向发生的时间进程和相关的神经反应的差异。结果发现,高特质焦虑者诱发出更大的N1,进一步发现恐惧图片比中性图片诱发更大的N1;而低特质焦虑者诱发了更大的N2,特质焦虑得分越低, N2波幅越大。结果初步说明高特质焦虑者加工早期对恐惧图片分配了较多的注意资源,并且其抑制执行功能可能受损;而低特质焦虑者较晚开始区分恐惧图片和中性图片。这些结果提供了支持认知-动机模型的新证据。  相似文献   
102.
In this study, (Gd1? x Nd x )2(Zr1? x Ce x )2O7 (0 ≤ x ≤ 0.5) ceramics have been prepared by pressureless sintering at 1973 K to investigate the influence of Nd and Ce co-doping on their electrical conductivity. The electrical conductivity of the ceramics was investigated by impedance spectroscopy measurements from 723 to 1173 K over the frequency range of 20 Hz to 2 MHz in air. The measured values obey the Arrhenius relation. For each composition, the grain conductivity gradually increases with increasing temperature from 723 to 1173 K. At a given temperature, it gradually decreases with increasing neodymium and cerium contents from x = 0 to 0.3; thereafter, the grain conductivity exhibits a slight increase with further increasing neodymium and cerium contents up to x = 0.5.  相似文献   
103.
ABSTRACT

Recently a novel type of epithelial cell has been discovered and dubbed the ‘scutoid’. It is induced by curvature of the bounding surfaces. We show by simulations and experiments that such cells are to be found in a dry foam subjected to this boundary condition.  相似文献   
104.

The thermal stability of highly disordered mechanically alloyed nanocrystalline NiAl has been evaluated. The reordering of disordered NiAl(Cr) shows extremely fast kinetics on isothermal annealing at and above 673K, while the process is quite sluggish below this temperature. On the other hand, significant reordering in NiAl(Fe) takes place even at 573K. A unique dependence of reordering on the grain growth of the nanophase is evident during thermal treatment. Rapid grain coarsening begins only as the absolute temperature approaches approximately 0.4 T m, where T m is the melting point of the aluminide.  相似文献   
105.
Abstract

Using human embryos in research remains a controversial issue, especially in Christian bioethics. Although the official Catholic stance rejects human embryonic stem cell research, Christian thinkers T. Peters, K. Lebacqz and G. Bennett support it. They endorse the 14-day Rule and argue that ex vivo embryos lack moral worth. I examine and challenge the 14-day Rule and location argument (in vivo/ex vivo). I develop a theory of holistic anthropology and intrinsic moral value for human embryos. I conclude that intrinsic moral value is not equal to full moral value, and therefore use of embryos in biomedical research is morally permissible.  相似文献   
106.
When people think about how a situation might have turned out differently, they tend to imagine counterfactual alternatives to their actions. We report the results of three experiments which show that people imagine alternatives to actions differently when they know about a reason for the action. The first experiment (n = 36) compared reason – action sequences to cause – effect sequences. It showed that people do not imagine alternatives to reasons in the way they imagine alternatives to causes: they imagine an alternative to an action more than an effect, and to a cause more than a reason. The second experiment (n = 214) and the third experiment (n = 190) both show that different sorts of reasons have different sorts of effects on how people imagine alternatives to actions. People imagine an alternative to an action (the protagonist went to a ball) less often when they know the reason for the action was an obligation (he had to participate in fundraising) compared to when they know about a weaker reason (he wanted to meet a famous violinist) or no reason. The second experiment shows the effect for a social obligation and the third experiment replicates and extends it to a health obligation. We interpret the results in terms of the possibilities that people keep in mind about actions and their reasons.  相似文献   
107.
Wason's standard 2-4-6 task requires discovery of a single rule and leads to around 20% solutions, whereas the dual goal (DG) version requires discovery of two rules and elevates solutions to over 60%. We report an experiment that aimed to discriminate between competing accounts of DG facilitation by manipulating the degree of complementarity between the to-be-discovered rules. Results indicated that perfect rule complementarity is not essential for task success, thereby undermining a key tenet of the goal complementarity account of DG facilitation. The triple heterogeneity account received a good degree of support since more varied triple exploration was associated with facilitatory DG conditions, in line with this account's prediction that task success is associated with the creative search of the problem space. The contrast class account (an extension of Oaksford & Chater's, 1994, iterative counterfactual model) was also corroborated in that the generation of descending triples was demonstrated to be the dominant predictor of DG success. We focus our discussion on conceptual ideas relating to the way in which iterative counterfactual testing and contrast class identification may work together to provide a powerful basis for effective hypothesis testing.  相似文献   
108.
The primary objective was to compare the MMPI-2 profiles for professional job applicants with corresponding profiles on the original MMPI. Male and female MMPI-2 profiles were also compared, and correlational and factor analyses were used to examine: A) Interscale correlations vis-à-vis item overlap, and B) The impact of K-corrections. The subjects were 82 auditor applicants, plus 212 sales and management applicants from an earlier study. The original MMPI was found to overpathologize applicant profiles. Male and female MMPI-2 profiles differed only on Mf. Scales L, K, and Hy formed a favorable cluster for job applicants, while F, Hs, Pt, Sc formed one unfavorable cluster—and D, Si a second. K-corrections consistently moved clinical scales in the direction of the favorable cluster.  相似文献   
109.
以2岁儿童为被试,探讨其在延迟满足情境中的自我控制能力发展的状况。结果表明:(1)2岁儿童已具有一定程度的自我控制能力,个体差异显著,性别差异不显著;(2)2岁儿童已能使用一定的延迟策略,包括问题解决、分心、寻求安慰、消极等待、寻求他人帮助、回避等,其中使用频率最高的是分心策略;(3)不同的策略对延迟时间有着不同的影响;(4)儿童对策略的使用不会因延迟满足情境的不同而出现显著差异。  相似文献   
110.
The primary purpose of this study was to examine whether empirically derived cluster profiles based on scores from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) predicted outcomes of surgery at 1 year for patients with low-back pain. On the basis of hierarchical cluster analysis of presurgery MMPI-2 scores for 60 patients, three interpretable and significant subgroups were formed. These consisted of a pathological/neurotic type, a double V-code type, and a normal type. The patents in the normal type were significantly more likely to report beneficial outcomes of surgery in terms of disability and pain than those in the other 2 types. These findings extend previous research and suggest (1) low-back surgery candidates are heterogeneous in their psychological profiles, and (2) MMPI-2 profiles are predictive of low-back surgery outcome. Future research should focus on identifying physiological substrates for these distinct profiles and investigating the effectiveness of presurgical psychological interventions based on profile type.  相似文献   
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