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881.
Weekly cycles in emotion were examined by combining item response modeling and spectral analysis approaches in an analysis of 179 college students' reports of daily emotions experienced over 7 weeks. We addressed the measurement of emotion using an item response model. Spectral analysis and multilevel sinusoidal models were used to identify interindividual differences in intraindividual cyclic change. Simulations and incomplete data designs were used to examine how well this combination of analysis techniques might work when applied to other practical data problems. Empirically, we found systematic individual differences in the extent to which individuals' emotions follow a weekly cycle, and in how such cycles are exhibited. Weekly cycles accounted for very little variance in day to day emotions at the individual level. Analytically, we illustrate how measurement, change, and interindividual difference models from different traditions may be combined in a practical manner to describe some of the complexities of human behavior. The authors gratefully acknowledge the support provided by grant T32 AG20500 from the National Institute on Aging in the preparation of this article. Special thanks to those at the Institute for Developmental and Health Research Methodology at the University of Virginia and to Paul De Boeck and the reviewers for helpful comments on earlier versions of this work.  相似文献   
882.
<维摩诘经>是印度早期大乘佛教的重要经典,在南北朝和隋唐时期广为流传,在佛教般若思想的发展中占有重要地位.该经蕴含着丰富的净土思想,明确提出了"心净则佛土净"这一著名命题.本文从菩萨取净土之目的与方法的角度,认为<维摩诘经>中菩萨取净土的目的是度化调伏众生,此即为"众生之类是菩萨佛土"的内含意蕴,还阐述分析了建立净佛国土之净土行和"心净则佛土净"思想.  相似文献   
883.
Two types of mechanisms have dominated theoretical accounts of efficient visual search. The first are bottom-up processes related to the characteristics of retinotopic feature maps. The second are top-down mechanisms related to feature selection. To expose the potential involvement of other mechanisms, we introduce a new search paradigm whereby a target is defined only in a context-dependent manner by multiple conjunctions of feature dimensions. Because targets in a multiconjunction task cannot be distinguished from distractors either by bottom-up guidance or top-down guidance, current theories of visual search predict inefficient search. While inefficient search does occur for the multiple conjunctions of orientation with color or luminance, we find efficient search for multiple conjunctions of luminance/size, luminance/shape, and luminance/topology. We also show that repeated presentations of either targets or a set of distractors result in much faster performance and that bottom-up feature extraction and top-down selection cannot account for efficient search on their own. In light of this, we discuss the possible role of perceptual organization in visual search. Furthermore, multiconjunction search could provide a new method for investigating perceptual grouping in visual search.  相似文献   
884.
王学钧 《学海》2005,2(6):77-81
自鲁迅以来,国内学界一直以为李伯元是个普通秀才,围绕着他是否因"屡举不第"而意见分歧.本文查证李伯元的功名其实是廪贡生.他只要愿意,凭廪贡生的功名就能出仕.但他放弃了科举之途和向官场发展的机会,选择了"下海"办报,成为晚清市民报人作家的先驱.  相似文献   
885.
There is a close correlation between long-term potentiation (LTP) in the synapses of lateral amygdala (LA) and fear conditioning in animals. We predict that reversal of LTP (depotentiation) in this area of the brain may ameliorate conditioned fear. Activation of group II metabotropic glutamate receptors (mGluR II) with DCG-IV induces depotentiation in the LA. The induction of depotentiation is independent of NMDA receptors, L-type Ca++ channels, and calcineurin activity, but requires presynaptic activity and extracellular Ca++. (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) depotentiation is accompanied by a decrease in the frequency but not the amplitude of miniature excitatory post-synaptic currents (mEPSCs) and could be mimicked by endogenously released glutamate. DCG-IV inhibited the release of glutamate evoked by 4-AP but not that evoked by ionomycin, suggesting that the effect of DCG-IV is not mediated by an action downstream of Ca++ entry. Intra-amygdala infusion of mGluR II agonist blocks the consolidation of fear memory measured with fear-potentiated startle. Taken together, the present results characterize the properties of DCG-IV depotentiation and reveal a close parallel between depotentiation in the amygdala slice and the reduction of conditioned fear in animals.  相似文献   
886.
887.
A conventional way to analyze item responses in multiple tests is to apply unidimensional item response models separately, one test at a time. This unidimensional approach, which ignores the correlations between latent traits, yields imprecise measures when tests are short. To resolve this problem, one can use multidimensional item response models that use correlations between latent traits to improve measurement precision of individual latent traits. The improvements are demonstrated using 2 empirical examples. It appears that the multidimensional approach improves measurement precision substantially, especially when tests are short and the number of tests is large. To achieve the same measurement precision, the multidimensional approach needs less than half of the comparable items required for the unidimensional approach.  相似文献   
888.
动觉监督早期介入对动作技能形成的影响   总被引:3,自引:0,他引:3  
通过人工动作技能项目和典型职业操作技能项目的训练活动,研究了动觉监督早期介入对动作技能形成的影响,结果表明早期进行动觉监督训练可以更为充分、有效地发挥动觉监督的作用,提高动作技能形成的成绩和效率。据此讨论了“视觉为主转化为动觉为主”监督机制观点的局限性,认为自觉的职业操作技能训练活动无须遵循这一结论;提出了含有动觉训练的职业操作技能训练模式。  相似文献   
889.
The authors examined clockwise and counterclockwise wheel-rotation responses to high- or low-pitched tones presented in participants' (N = 96, Experiment 1; N = 48, Experiment 2; N = 48, Experiment 3) left and right ears. In Experiment 1, a Simon effect (fastest responding when tone location and direction of wheel turn corresponded) was obtained when participants' hands were at the top or middle of the wheel but not at the bottom. With the bottom hand placement, a Simon effect was induced by instructions emphasizing hand movements but not by instructions emphasizing wheel movements (Experiment 2), and by a visual cursor controlled by the wheel but not one triggered by the response (Experiment 3). The results of the experiments showed that the nature of the task and the instructed action goal influence the direction of the Simon effect.  相似文献   
890.
We examined clinically depressed (CD; n = 16), previously depressed (PD; n = 19) and never depressed (ND; n = 18) individuals on 13 theoretically selected Rorschach (Exner, 1993; Rorschach, 1942) variables and on the Beck Depression Inventory (BDI; Beck, Rush, Shaw, & Emery, 1979). The group assignment was made according to the criteria of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994). We tested 2 contradictory models for depressive vulnerability, Beck's (Clark & Beck, 1999) and Miranda and Persons's (1988; Persons & Miranda, 1992), in a planned comparison design with focused contrasts. The CDs significantly contrasted the combined group of NDs and the PDs in a pathological direction on 8 of the 13 Rorschach variables and on the BDI. However, the combined group of CDs and PDs also significantly contrasted the NDs in a pathological direction on 3 of these Rorschach variables and on the BDI. In addition, logistic regression analyses indicated that Rorschach indexes significantly improved the prediction of major depression above and beyond that achieved by the BDI. The findings show that the Rorschach method was able to identify (a) cognitive and aggressive disturbances that are present in individuals who are actively depressed but not in individuals who have been depressed in the past or never been depressed and (b) affective and coping disturbances that are present in depressed individuals and to some degree in PD individuals but not in individuals who have not experienced depression. We discuss the scanty evidence of psychological disturbances in PD individuals, as measured with the Rorschach, in relation to the mood-state dependent hypothesis of Miranda and Persons (1988; Persons & Miranda, 1992).  相似文献   
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