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171.
We propose the use of thickness-twist (TT) and face-shear (FS) vibration modes of an AT-cut quartz crystal plate resonator for simultaneous determination of the inertia and stiffness of a thin film deposited on a crystal surface. A theoretical analysis using Mindlin's first-order theory for crystal plates is performed to demonstrate the idea. Expressions for the stiffness ratio and mass ratio between the thin film and the resonator are presented in terms of frequency shifts of FS and TT modes, which are experimentally measurable. A numerical example is given.  相似文献   
172.
目前社会阶层分化进程中的医患关系比较紧张,医患信息行为起了很大作用.由于历史原因多数医师未能认识到医患信息行为对医患沟通及医患关系的影响.患者作为医疗信息掌握的弱势群体,其对从医师处获得信息的依赖将长期存在,医师与患者信息行为必然相互影响.针对信息行为建立相应的培训及评价机制是十分必要的.  相似文献   
173.
With intensively collected longitudinal data, recent advances in the experience-sampling method (ESM) benefit social science empirical research, but also pose important methodological challenges. As traditional statistical models are not generally well equipped to analyze a system of variables that contain feedback loops, this paper proposes the utility of an extended hidden Markov model to model reciprocal the relationship between momentary emotion and eating behavior. This paper revisited an ESM data set (Lu, Huet, &; Dube, 2011 Lu, J., Huet, C., &; Dubé, L. (2011). Emotional reinforcement as a protective factor for healthy eating in home settings. The American Journal of Clinical Nutrition, 94(1), 254261. http://dx.doi.org/10.3945/ajcn.110.006361[Crossref], [PubMed], [Web of Science ®] [Google Scholar]) that observed 160 participants' food consumption and momentary emotions 6 times per day in 10 days. Focusing on the analyses on feedback loop between mood and meal-healthiness decision, the proposed reciprocal Markov model (RMM) can accommodate both hidden (“general” emotional states: positive vs. negative state) and observed states (meal: healthier, same or less healthy than usual) without presuming independence between observations and smooth trajectories of mood or behavior changes. The results of RMM analyses illustrated the reciprocal chains of meal consumption and mood as well as the effect of contextual factors that moderate the interrelationship between eating and emotion. A simulation experiment that generated data consistent with the empirical study further demonstrated that the procedure is promising in terms of recovering the parameters.  相似文献   
174.
Differences in reasoning styles between Chinese and European Americans held even when controlling for the language of testing. Bilingual Chinese organized objects in a more relational and less categorical way than European Americans, whether tested in English or in Chinese. Thus, culture affects categorization independent of the testing language. Nevertheless, language affected some Chinese bilinguals' categorization. The responses of Chinese from the Mainland and Taiwan were more relational when tested in Chinese than when tested in English. Responses of Chinese from Hong Kong and Singapore were equally relational when tested in Chinese and in English. Age and context of learning English are discussed to explain the differential language effects among different Chinese groups. Theoretical and methodological implications are discussed.  相似文献   
175.
Training-induced and electrically induced potentiation in the neocortex   总被引:3,自引:0,他引:3  
Long-term potentiation (LTP) shares many properties with memory and is currently the most popular laboratory model of memory. Although it has not been proven that memory is based on an LTP-like mechanism, there is evidence that learning a motor skill can induce LTP-like effects. This evidence was obtained in a slice-preparation experiment, which precluded within-animal comparisons before and after training. In the present experiments, Long-Evans rats were unilaterally trained to acquire a forelimb reaching and grasping skill. Evoked potentials were found to be larger in motor cortex layer II/III in the trained, compared to the untrained, hemisphere in slice, acute, and chronic preparations. Consistent with previous research, the trained hemisphere was less amenable to subsequent LTP induction. Furthermore, the application of either LTP- or LTD-inducing stimulation during the training phase of the reaching task disrupted the acquisition of the skill, providing further evidence that memory may be based on an LTP mechanism.  相似文献   
176.
Positive risk-taking is a crucial element of individual creativity and social development. However, little is known regarding the relation between individual neural differences and positive risk-taking. In addition, critical thinking (CT) and gender have been proven to be two important individual-specific factors associated with risk-taking behaviour, and different levels of CT and gender may have diverse effects on the relationship between brain structure and positive risk-taking. The present study examined the relationship between positive risk-taking and regional grey matter volume (rGMV) in 292 healthy participants. The results showed that positive risk-taking was significantly positively associated with the rGMV of the posterior cingulate cortex (PCC). In addition, this study investigated individual differences in critical thinking and found that it moderated the relationship between rGMV and positive risk-taking. Individuals with lower CT had a stronger association between rGMV and positive risk-taking. Further analysis showed that for males, a greater rGMV was significantly linked to higher positive risk-taking tendency. These findings suggest that PCC evaluates risk and serves as a behavioural adaptation hub for positive risk-taking. This study thereby contributes to the literature on individual differences in brain structure and risk-taking by elucidating the moderating effects of CT and gender in healthy adults.  相似文献   
177.
语义的自动加工和选择性注意对Stroop效应的影响   总被引:3,自引:1,他引:2  
本实验用正常人和聋哑人作被试进行比较,试图探讨语义的自动加工和选择性注意对Stroop效应的影响。将“红”“绿”“黄”“蓝”四个汉字中的每一个都用这四种颜色中的三种写成,然后按着事先排列好的顺序,分组呈现,并且在两种条件下分别要求被试延迟不同的时间进行反应,一种是刺激呈现前就告诉被试对“字”或“色”反应;另一种是刺激呈现后间隔不同的时间再向被试提出对“字”或“色”反应。实验结果发现,聋哑人和正常人在色—字干扰任务作业上没有明显的差异,说明语义的自动加工是一个普遍现象;而选择性注意能在很大的程度上改善被试的作业成绩,但颜色命名仍比字词反应困难;Stroop效应在延迟反应条件下发生变化,这种变化说明Stroop效应与记忆过程有联系。  相似文献   
178.
从汉字识别看视觉信息检测的整体优先性   总被引:4,自引:0,他引:4  
本实验以汉字组成的复合汉字为材料研究了不同视角下辨别整体结构和辨别局部特性的反应时差异。实验发现,在正常情况下对整体的辨别反应时要显著低于对局部进行辨别的反应时,并且对象的不同大小对这种差异没有显著影响。这一结果表明整体和局部的“相对大小”不是造成反应时差异的主要原因,提示视觉信息检测是一个从大范围的整体到局部的过程,即存在整体优先性。实验还发现在作为局部的汉字和构成整体的复合字相同时,无论注意对象是局部还是整体,反应时均较不同时为小,这一结果表明整体和局部的作用是双向的。  相似文献   
179.
本实验研究通过把汉字拆为其有机的组成成分,最少2个最多5个,在各成分顺序排列或随机排列两种条件下呈现给被试,要他们组合出原来汉字的方法对表象操作的容量和策略进行了初步的探讨。实验结果表明表象操作的容量是相当有限的,执行最优加工的容量为2—3个,上限约为4—5个。加工容量随操作复杂程度的高低可略有变化。结果还表明在本实验条件下系统对表象各成分的操作采取的是并行的同时加工,这种并行加工能大大提高表象加工的效率。  相似文献   
180.
Marx extrapolated the relations of production of the factories of his time into his predictions about the development of the working class. These predictions are among the most important theses of Marxism-Leninism relative to the socialist world-revolution which the working class was to carry out. The physics of Marx' era was not very developed. Marx could have no inkling of the future development of physics and of its application to technology. This is why his predictions had to be in simple and direct proportion to the development of the relations of production of the time. Industry developed — thanks in part to the development of physics — in ways other than Marx had suspected. The use of modern physics, leading to cybernetics and automation, gradually changed the workers from forces of production to supervisory engineers. Were one to undertake today an extrapolation like that which Marx carried out, one would have to see as highly probable the disappearance of the very working class that Marx saw as carrying out the world-revolution.  相似文献   
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