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573.
A thorough TEM analysis has been carried out to study the dislocations cutting into γ′ phase in a single-crystal superalloy during uniaxial tensile creep under high-temperature and low-stress conditions. It is proved that the a〈100〉 edge superdislocation originates from the interfacial a〈100〉 dislocations and moves into the γ′ phase by pure climbing. And the dissociation of the a〈100〉 superdislocation core into two a/2〈101〉 superpartial dislocations during uniaxial tensile creep has been identified by HRTEM method for the first time.  相似文献   
574.
Many animals modify behavioural decisions based on information they have previously acquired. Contest behaviour is often affected by previous contest experiences: individuals behave more and less aggressively after a victory and defeat, respectively (winner/loser effect). Individuals in the field sometimes encounter multiple competitors in quick succession, but whether these experiences interact to influence each other’s importance is unclear. We tested five hypotheses for experience interaction (no interaction, retroactive interference, proactive interaction, reinforcement and diminishing returns) using Kryptolebias marmoratus. Focal individuals were paired up with opponents having the same 1-month contest outcome (1 month before the experiment), as this difference in actual or perceived fighting ability has been shown to affect the fish’s response to new experiences. We gave the focal individual of a pair a winning or losing experience on day 1. Then both fish of the pair received the same winning, losing or no-contest experience on day 2. Then we organised fights between the two. The effect of a day-1 losing experience did depend on the fish’s actual or perceived fighting ability: one-month losers readily showed loser effects from the day-1 losing experience, irrespective of the day-2 experience (i.e. no interaction between day-1 and day-2 experiences). One-month winners, however, only showed loser effects from a day-1 losing experience when the day-2 experience was also a loss (i.e. reinforcement). Day-1 winning experiences did not interact with day-2 experiences in 1-month losers or winners. Therefore, multiple experiences sometimes reinforce each other, but how they combine to influence behaviour depends on an individual’s actual or perceived fighting ability.  相似文献   
575.
The morphological constituents of English compounds (e.g., “butter” and “fly” for “butterfly”) and two-character Chinese compounds may differ in meaning from the whole word. Subjective differences and ambiguity of transparency make judgments difficult, and a computational alternative based on a general model might be a way to average across subjective differences. In the present study, we propose two approaches based on latent semantic analysis (Landauer & Dumais in Psychological Review 104:211–240, 1997): Model 1 compares the semantic similarity between a compound word and each of its constituents, and Model 2 derives the dominant meaning of a constituent from a clustering analysis of morphological family members (e.g., “butterfingers” or “buttermilk” for “butter”). The proposed models successfully predicted participants’ transparency ratings, and we recommend that experimenters use Model 1 for English compounds and Model 2 for Chinese compounds, on the basis of differences in raters’ morphological processing in the different writing systems. The dominance of lexical meaning, semantic transparency, and the average similarity between all pairs within a morphological family are provided, and practical applications for future studies are discussed.  相似文献   
576.
This research aimed to investigate educators' implicit perspectives on wisdom in order to compare interpersonal and intrapersonal perspectives and to help identify similarities or differences between these two theoretical perspectives. A total of 56 educators in Taiwan were interviewed individually. We utilised the grounded theory method to analyse the qualitative data. Results showed that both interpersonal and intrapersonal perspectives converged on four core components of wisdom: intrapsychic integration, actions in service of problem solving and ideal implementation, positive results and feedback and adjustments. The interpersonal perspective referred to external characteristics, and admiration and influence, whereas the intrapersonal perspective included greater detail about intrapsychic integration and action strategies than did the interpersonal perspective. We close with a discussion both of how wisdom appears to span across different fields and how the present results might feed into the teaching of wisdom in schools.  相似文献   
577.
The purpose of this study was twofold: (1) to analyze the effects of both personality and environmental variables on the imagination of video/film major university students; and (2) to test the mediator effect resulting from the variable of social climate. The results of this study supported both indicators of imaginative capabilities and environmental influences. The hypothesis of the study—that the variable of social climate mediates the effects of personality/environmental predictors and both types of imagination—was partially supported. The structural model also showed that most personality traits have direct effects on imagination, whereas most environmental predictors have indirect effects. Practical applications of this study were suggested, future inquiries were discussed, and limitations were acknowledged.  相似文献   
578.
Through analyzing response latencies, errors, and self-repairs in Mandarin, this investigation explores how monolingual, bilingual, and trilingual adults process their speech production differently using cognitive control mechanisms. In this study we conducted two experiments involving speech production in Mandarin. In the two experiments, 81 adults participated and were categorized into three groups: Mandarin monolingual, Hakka-Mandarin bilingual, and Hakka-Mandarin-Minnan trilingual. In Experiment 1 (unpreprogrammed task), each subject read 250 targets that were presented on a computer screen, one at a time, using E-prime; in Experiment 2 (preprogrammed task), each subject read 466 targets printed on A4 paper. Experiment 1 showed that bilinguals and trilinguals outperformed monolinguals in every aspect examined in this research, revealing the presence of bilingual and trilingual advantages in inhibitory control. Interestingly, in Experiment 2, we found a more complex pattern of results: a trilingual advantage in attentional control occurred during L2 production in terms of the number of errors and error correction; however, the bilingual group did not maintain this advantage in the task requiring attentional control. These experimental results revealed that the differences between the language groups became clearer when the inhibitory control demands increased and that compared with the trilingual advantage, the bilingual advantage in inhibitory control emerged in more limited contexts.  相似文献   
579.
返回抑制(inhibition of return, IOR)与情绪刺激都具有引导注意偏向、提高搜索效率的特点, 但二者间是否存在一定的交互作用迄今为止尚不明确。研究采用“线索-目标”范式并在视听双通道呈现情绪刺激来考察情绪刺激的加工与IOR的交互作用。实验1中情绪刺激以单通道视觉面孔或一致的视听双通道呈现, 实验2通过在视听通道呈现不一致的情绪刺激进一步考察视听双通道情绪一致刺激对IOR的影响是否是由听觉通道一致的情绪刺激导致的, 即是否对听觉通道的情绪刺激进行了加工。结果发现, 视听双通道情绪一致刺激能够削弱IOR, 但情绪不一致刺激与IOR之间不存在交互作用, 并且单双通道的IOR不存在显著差异。研究结果表明仅在视听双通道呈现情绪一致刺激时, 才会影响同一阶段的IOR, 这进一步支持了IOR的知觉抑制理论。  相似文献   
580.
Xamoterol, a partial β(1)-adrenergic receptor agonist, has been reported to impair the retrieval of hippocampus-dependent spatial reference memory in rats. In contrast, xamoterol restores memory retrieval in gene-targeted mice lacking norepinephrine (NE) and in a transgenic mouse model of Down syndrome in which NE levels are reduced. Restoration of retrieval by xamoterol in these two models complements the observation that NE and β(1) signaling are required for hippocampus-dependent retrieval of contextual and spatial reference memory in wild-type mice and rats. Additional evidence indicates that cAMP-mediated PKA and Epac signaling are required for the retrieval of hippocampus-dependent memory. As a result, we hypothesized that xamoterol has effects in addition to the stimulation of β(1) receptors that, at higher doses, act to counter the effects of β(1) signaling. Here we report that xamoterol-induced disruption of memory retrieval depends on β(2)-adrenergic receptor signaling. Interestingly, the impairment of memory retrieval by xamoterol is blocked by pretreatment with pertussis toxin, an uncoupling agent for G(i/o) signaling, suggesting that β(2) signaling opposes β(1) signaling during memory retrieval at the level of G protein and cAMP signaling. Finally, similar to the time-dependent roles for NE, β(1), and cAMP signaling in hippocampus-dependent memory retrieval, xamoterol only impairs retrieval for several days after training, indicating that its effects are also limited by the age of the memory. We conclude that the disruption of memory retrieval by xamoterol is mediated by G(i/o)-coupled β(2) signaling, which opposes the G(s)-coupled β(1) signaling that is transiently required for hippocampus-dependent emotional memory retrieval.  相似文献   
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