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31.

We report metastable photoinduced volume expansion (hyperexpansion) of up to 10 µm in height and several millimetres in diameter for the chalcogenide glass As 2 S 3 . This is an order of magnitude larger than reported to date in any material, including chalcogenide glasses. We suggest a model for the effect and propose that its origin is similar to the origin of photoinduced anisotropy in glassy chalcogenides proposed earlier. The model is based on the anisotropic chemical bonding found in most chalcogenide glasses; the anisotropy arises from the fact that chalcogen atoms exhibit both strong covalent bonding and weak van der Waals bonding. The origin of the photoinduced volume changes (expansion and contraction) is in a thermally induced diffusion, or athermal tunnelling, of photoexcited chalcogen atoms, with possible subsequent sublimation from the sample surface. The primary role of hyperpolarizable van der Waals bonds is supported by the absence of photoinduced volume changes in the chalcogenide glass Ga 1.4 La 0.6 S 3, in which chalcogen atoms do not bond via van der Waals bonds.  相似文献   
32.
The authors focused on individual working memory (WM) capacity and examined its effect on postural control. Participants were 79 young volunteers split into two groups of low- and high WM span, based on scores from the Reading Span Test. The length of unrest was measured in the following conditions: double-leg standing as a single (D-S) task, single-leg standing as a single (S-S) task, double-leg standing as a dual (D-D) task, and single-leg standing as a dual (S-D) task. Regarding inte-group comparisons, total length was prolonged significantly between the low- and the high-span groups but only on the S-D task. The present results revealed that dual-task interference emerged in the low-span group when in a more unstable posture.  相似文献   
33.
This study examined the effect on positive and negative emotions in Japanese college students of mentally subtracting grateful events. Participants (N = 62) were randomly assigned to one of the following three conditions: (a) writing with surprise the ways that a positive thing or event might never have happened or might never have been part of life (the mentally subtracting a present good [MS] group), (b) writing without surprise the ways in which a positive thing or event happened easily or was certain to become a part of life (the counting gratitude group), and (c) no writing control. The results of analysis of variance showed that the MS group experienced significantly increased positive emotion and decreased negative emotion between pre‐test and post‐test. Furthermore, the MS group showed significantly greater positive emotion than the control group at post‐test. Surprise mediated the effects of the MS group intervention on positive emotion but not on negative emotion. Issues related to gratitude induction and mediation of surprise are discussed.  相似文献   
34.
Using focus groups, we examined support and opposition for Donald Trump prior to the 2016 presidential election. When ingroup members participate in discussion, this conversation alone typically strengthens and intensifies members’ initial attitudes. We used a pre‐ to post‐focus‐group questionnaire to assess attitudes toward Trump, his campaign, and policies. We argue that group polarization influenced people’s opinions about Trump such that attitudes became more extreme after discussion with like‐minded individuals. We report changes for Trump nonsupporters for which group polarization occurred on attitudes toward illegal immigration, political correctness, the military, women, and veterans after the group discussion. For each, level of support for Trump’s views decreased. To further explore potential psychological mechanisms associated with group polarization, we employed network science methods to examine the structure of the language associated with these issues and identify potential drivers of attitude change. Results provide some support for a common mechanism for group polarization, which may be driven by language dynamics specific to individual attitudes.  相似文献   
35.
Abstract: To investigate mechanisms for perceiving the duration of an auditory event, an effect of perceptual grouping upon perceived duration was studied psychophysically. In the first experiment, the perceived duration of a spoken word was measured under three conditions of acoustic continuity (i.e., (a) intact, (b) noise‐replaced, and (c) gap‐replaced) as a function of the duration of the target stimulus. Under the noise‐replaced condition, a portion of the target stimulus was physically replaced with a noise burst. Under the gap‐replaced condition, the replacement was made with a gap. The gap‐replacement resulted in a prominent shrinkage of the perceived duration. In the case of noise‐replacement, the amount of shrinkage was moderate but highly significant, although the word employed was perceived to be phonetically intact. Independent of this effect of replacement, the amount of shrinkage was also affected by the physical duration of the target stimulus. The second experiment tested an effect of noise replacement on the perceived duration of a tone burst. In this case, the noise replacement also shrunk the perceived duration of the non‐speech stimulus. This noise‐induced shrinkage could be regarded as being general for the auditory duration. The phenomenon is discussed in relation to a revised model for perceived duration.  相似文献   
36.
The prototype effect in face recognition: Extension and limits   总被引:2,自引:0,他引:2  
The prototype effect in face recognition refers to a tendency to recognize the face corresponding to the central value of a series of seen faces, even when this central value or prototype has not been seen. Five experiments investigated the extension and limits of this phenomenon. In all the experiments, participants saw a series of faces, each one in two or more different versions or exemplars, and then performed a recognition test, including seen and unseen exemplars and the unseen prototype face. In Experiment 1, a strong prototype effect for variations in feature location was demonstrated in oldness ratings and in a standard old/new recognition test. Experiments 2A and 2B compared the prototype effect for variations in feature location and variations in head angle and showed that, for the latter, the prototype effect was weaker and more dependent on similarity than for the former. These results suggest that recognition across feature variations is based on an averaging mechanism, whereas recognition across viewpoint variations is based on an approximation mechanism. Experiments 3A and 3B examined the limits of the prototype effect using a face morphing technique that allows a systematic manipulation of face similarity. The results indicated that, as the similarity between face exemplars decreases to the level of similarity between the faces of different individuals, the prototype effect starts to disappear. At the same time, the prototype effect may originate false memories of faces that were never seen.  相似文献   
37.
Normal vascular tonus and permeability of the microcirculatory network is mediated by catecholamines, histamine and serotonin. Following electroconvulsive treatment (ECT), histamine did not provoke local vasodilatation. The inhibition was further potentiated by drugs which prevent the enzymatic or physical inactivarion of free catecholamines and by locally administered norepinephrine. This system became conditioned to a visual stimulus when rats were presented in six consecutive occasions with the visual stimulus preceedingly coincided with the administration of ECT. In the conditioned rats, light alone inhibited the histamine-induced vasodilatation, and this inhibition was potentiated by sub-effective doses of injected norepinephrine and by drugs which prevent the enzymatic or physical inactivation of catecholamines. Sedatives, antidepressants, MAO inhibitors and the chlorpromazine-type agents as well as the psychotomimetic drugs characteristically influence either the acquisition or the extinction of the conditioned reflex. Results suggest that the obtained conditioning of the microcirculatory functions are mediated by tie centrally released catecholamines.  相似文献   
38.
A review of the literature on children's use of relative clause constructions reveals many contradictory findings. The suggestion is that some studies fail to take into account the two factors of embeddedness (role of complex noun phrase within the sentence) and focus (role of head noun in the relative clause). The experiment reported here attempted to reconcile the disparate findings and extend the range of constructions examined. 114 children between the ages of 3 and 7 served as subjects in a test of comprehension using an act-out procedure of 9 different relative clause sentences that exhaust the possible combination of 3 roles of the complex noun phrase in the sentence and 3 roles that the head noun plays within the relative clause (in each case, subject, driect object, and indirect object). All constructions were understood better with increasing age of the children sex and sentence set were nonsignificant variables. The results reveal a difficulty in ordering of the 9 types of construction that is in keeping with a prediction based on surface structure processing strategies.This research was supported by grant No. BNS73-09150 from the National Science Foundation to Professor Roger Brown.  相似文献   
39.
40.
Flashbulb memories are vivid memories of the details surrounding the discovery of an emotional event. We investigated whether the nuclear accident that occurred in Japan in 1999 produced flashbulb memories among people who lived near the accident site. A questionnaire was distributed twice (approximately 3 weeks after the accident and 1 year later) to (1) the residents of the communities surrounding the accident site, (2) the students at a university near the accident site, and (3) the students at two universities far away from the accident site. Flashbulb memory holders were defined as those individuals who showed consistent memories between test and retest. The results indicated that only a small percentage of participants formed flashbulb memories. Further, no age-related decline was found. Flashbulb memories were distinguished by perfect or near perfect scores on four attributes: source, place, activity, and people. The results also indicated that the ratings on emotional reactions, personal consequentiality, and surprise did not differentiate between the flashbulb and non-flashbulb memory holders. In contrast, the flashbulb memory holders reported rehearsing more than the non-flashbulb memory holders. These results supported the notion that flashbulb memories are formed through rehearsal rather than at encoding. However, it is also possible that rehearsal was a result of the flashbulb memory.  相似文献   
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