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61.
肥胖是体内脂质过度沉积的一种状态,其不仅可引起糖脂代谢紊乱、胰岛素抵抗,从而继发糖尿病、高血压、冠心病等疾病,而且当脂质水平超过脂肪细胞的储存容量及出现胰岛素抵抗时,血液中游离脂肪酸含量会随之升高,进而可引起脂质在心脏的异位沉积.沉积于心肌细胞的脂质可进一步通过神经酰胺、内质网应激等机制影响心肌细胞的结构和功能,最终导致心力衰竭的发生.但肥胖所致心肌脂毒性具体机制不明,本文就肥胖所致心肌脂毒性可能机制做一综述. 相似文献
62.
Weiping Hu Baojun Wu Xiaojuan Jia Xinfa Yi Chunyan Duan Winter Meyer James C. Kaufman 《创造性行为杂志》2013,47(1):3-21
The “Learn to Think” (LTT) Intervention Program was developed for raising thinking abilities of primary and secondary school students. It has been implemented in more than 300 schools, and more than 200,000 students took part in the experiment over a 10‐year span. Several longitudinal intervention studies showed that LTT could promote the development of students' thinking ability, learning motivation, and learning strategy as well as raise academic performance in primary schools. This article describes a study of the influence and the delayed effects of LTT on the scientific creativity of secondary school students. One hundred and seven students were selected from a secondary school, 54 of them participated in the LTT every 2 weeks and the rest had not. The intervention lasted 2 years, and the delayed effect was explored half a year after terminating the intervention. The Scientific Creativity Test for Secondary School Students was used four times from pre‐test to delayed post‐test. The results indicated that the LTT did promote the development of scientific creativity of secondary school students, and the effects on the scientific creativity were not necessarily immediate, but tended to be long‐lasting. 相似文献
63.
We investigated how age of faces and emotion expressed in faces affect young (n=30) and older (n=20) adults’ visual inspection while viewing faces and judging their expressions. Overall, expression identification was better for young than older faces, suggesting that interpreting expressions in young faces is easier than in older faces, even for older participants. Moreover, there were age-group differences in misattributions of expressions, in that young participants were more likely to label disgusted faces as angry, whereas older adults were more likely to label angry faces as disgusted. In addition to effects of emotion expressed in faces, age of faces affected visual inspection of faces: Both young and older participants spent more time looking at own-age than other-age faces, with longer looking at own-age faces predicting better own-age expression identification. Thus, cues used in expression identification may shift as a function of emotion and age of faces, in interaction with age of participants. 相似文献
64.
Tae Wook Heo Yi Wang Saswata Bhattacharya Xin Sun Shenyang Hu Long-Qing Chen 《Philosophical Magazine Letters》2013,93(2):110-121
We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures. 相似文献
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66.
利用有限的认知资源应对多变的环境刺激,选择性注意和情绪加工一个重要的共同机制是优先化关键信息的加工。尽管情绪性刺激(特别是威胁刺激)能够影响注意资源的分配,但一些关键脑区(如杏仁核)的对情绪性刺激的加工是自动化过程还是受到注意调节一直是个有争议的问题。最新的结合高时间分辨率和高空间分辨率的神经生理记录研究表明,情绪加工的重要核团,杏仁核,对情绪性刺激的加工包含早期快速的不依赖于注意资源和认知加工负荷的自动化加工成分和晚期受到额-顶叶皮层自上而下的注意调控成分,这种功能整合证实杏仁核情绪性加工存在并行的皮层下和皮层通路。 相似文献
67.
We show that perceived size of visual stimuli can be altered by matches between the contents of visual short-term memory and stimuli in the scene. Observers were presented with a colour cue (to hold in working memory or to merely identify) and subsequently had to indicate which of the two different-coloured objects presented simultaneously on the screen appeared bigger (or smaller). One of the two objects for size judgements had the same colour as the cue (matching stimulus) and the other did not (mismatching stimulus). Perceived object size was decreased by the reappearance of the recently seen cue, as there were more size judgement errors on trials where the matching stimulus was physically bigger (relative to the mismatching stimulus) than on trials where the matching stimulus was physically smaller. The effect occurred regardless of whether the visual cue was actively maintained in working memory or was merely identified. The effect was unlikely generated by the allocation of attention, because shifting attention to a visual stimulus actually increased its perceived size. The findings suggest that visual short-term memory, whether explicit or implicit, can decrease the perceived size of subsequent visual stimuli. 相似文献
68.
Colin Camerer Yi Xin Clarice Zhao 《Journal of the experimental analysis of behavior》2024,121(1):108-122
This article applies a two-process “neural autopilot” model to field data. The autopilot model hypothesizes that habitual choice occurs when the reward from a behavior has low numerical “doubt” (i.e., reward prediction errors are small). The model toggles between repeating a previous choice (habit) when doubt is low and making a goal-directed choice when doubt is high. The model has ingredients established in animal learning and cognitive neuroscience and is simple enough to make nonobvious predictions. In two empirical applications, we fit the model to field data on purchases of canned tuna and posting on the Chinese social media site Weibo. This style of modeling is called “structural” because there is a theoretical model of how different variables influence choices by agents (the “structure”), which tightly restricts how hidden variables lead to observed choices. There is empirical support for the model, more strongly for tuna purchases than for Weibo posting, relative to a baseline “reduced-form” model in which current choices are correlated with past choices without a mechanistic (structural) explanation. An interesting set of predictions can also be derived about how consumers react to different kinds of changes in prices and qualities of goods (this is called “counterfactual analysis”). 相似文献
69.
厌腻感是指消费者对连续或过量消费同一产品或服务的效用感、享乐感或满意度下降, 负面感知逐步抑制正面感知的主观情绪体验。为缓解或防止厌腻感的产生, 消费者会采取品牌转换、多样化寻求、控制消费周期等行为, 因此厌腻感已成为企业或店铺培养顾客忠诚的主要障碍。国外文献分别从厌腻感的生成过程、功能反应、知觉状态和属性感知等方面, 划分厌腻类型; 剖析了厌腻感生成的享乐适应、边际效用递减、认知失调以及最佳刺激水平等理论原理及机理; 探讨了生理厌腻感和心理厌腻感生成的诱发因素及影响效应; 验证了外部因素和个体因素的调节作用; 同时探讨了消费者缓解或防止厌腻感的主要策略及行为反应。最后对现有文献的研究思路、特点和不足进行了评述, 提出了未来研究方向。 相似文献
70.