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Emotion theorists have long debated whether valence, which ranges from pleasant to unpleasant states, is an irreducible aspect of the experience of emotion or whether positivity and negativity are separable in experience. If valence is irreducible, it follows that people cannot feel happy and sad at the same time. Conversely, if positivity and negativity are separable, people may be able to experience such mixed emotions. The authors tested several alternative interpretations for prior evidence that happiness and sadness can co-occur in bittersweet situations (i.e., those containing both pleasant and unpleasant aspects). One possibility is that subjects who reported mixed emotions merely vacillated between happiness and sadness. The authors tested this hypothesis in Studies 1–3 by asking subjects to complete online continuous measures of happiness and sadness. Subjects reported more simultaneously mixed emotions during a bittersweet film clip than during a control clip. Another possibility is that subjects in earlier studies reported mixed emotions only because they were explicitly asked whether they felt happy and sad. The authors tested this hypothesis in Studies 4–6 with open-ended measures of emotion. Subjects were more likely to report mixed emotions after the bittersweet clip than the control clip. Both patterns occurred even when subjects were told that they were not expected to report mixed emotions (Studies 2 and 5) and among subjects who did not previously believe that people could simultaneously feel happy and sad (Studies 3 and 6). These results provide further evidence that positivity and negativity are separable in experience. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Feng Michelle C.; Courtney Christopher G.; Mather Mara; Dawson Michael E.; Davison Gerald C. 《Canadian Metallurgical Quarterly》2011,26(3):752
Previous studies reveal age by valence interactions in attention and memory, such that older adults focus relatively more on positive and relatively less on negative stimuli than younger adults. In the current study, eyeblink startle response was used to measure differences in emotional reactivity to images that were equally arousing to both age groups. Viewing positive and negative pictures from the International Affective Picture System had opposite effects on startle modulation for older and younger adults. Younger adults showed the typical startle blink pattern, with potentiated startle when viewing negative pictures compared to positive pictures. Older adults, on the other hand, showed the opposite pattern, with potentiated startle when viewing positive pictures compared to viewing negative and neutral pictures. Potential underlying mechanisms for this interaction are evaluated. This pattern suggests that, compared with younger adults, older adults are more likely to spontaneously suppress responses to negative stimuli and process positive stimuli more deeply. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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H. Reiss F. Schmaderer G. Wahl B. Ziegenbein R. Caps 《International Journal of Thermophysics》1987,8(2):263-280
This paper describes first experimental steps of an attempt to replace evacuated multifoils by metal-coated dielectric fibers as a new superisolation. Calculations of the Rosseland mean of spectral extinction coefficients for thin highly relective fibers show that radiation transport can be reduced to the same extent that is achievable with multifoils. Experimental results of extinction coefficients and thermal conductivity of Al-coated glass fibers are reported. Apparently, the metal coating does not increase seriously the small solid thermal conductivity of pure glass fibers. The procedure for optimizing this insulation is thus reduced to an optimization of its extinction properties. 相似文献
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Chen Zhanheng 《中国稀土信息(英文版)》2014,(5)
<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586 相似文献
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给出了泛函微分方程x(t)=f(t,xx)及其被扰动方程x(t)=f(t,xt)+g(t,xt)的零解为完全全局渐近稳定的一个Razumikhin定理;推广和改进了有关结果 相似文献
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