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171.
Jianming Zeng Chenglu Lin Zhitang Song Kun Li Jinhua Li 《Philosophical Magazine Letters》2013,93(2):119-124
Lead zirconate titanate (PZT) (Pb(Zr0.52Ti0.48)O3) and barium titanate (BaTiO3) thin films have been successfully prepared using a novel sol-gel- hydrothermal (SG-HT) technique at low temperatures, which involves a combination of the conventional sol-gel process and a hydrothermal method. Highly (111)-oriented PZT thin films with a single perovskite phase and polycrystalline BaTiO thin films with well developed crystallites were obtained at a processing temperature as low as 1600C. The microstructural characteristics demonstrate that the SG-HT-derived PZT and BaTiO3 thin films with good crystallinity and surface morphology are converted from the amorphous phase to the desired perovskite phase on platinum-coated and bare silicon substrates at a low processing temperature of 100-200 C. These results suggest that the SGHT technique, which is of great significance because of its low processing temperature, will become a potential and promising process for fabricating PZT, BaTiO3 and other oxide thin films. 相似文献
172.
Animals may memorise spatial and social information for many months and even years. Here, we investigated long-term memory of hierarchically ordered relationships, where the position of a reward depended on the relationship of a stimulus relative to other stimuli in the hierarchy. Seventeen greylag geese (Anser anser) had been trained on discriminations between successive pairs of five or seven implicitly ordered colours, where the higher ranking colour in each pair was rewarded. Geese were re-tested on the task 2, 6 and 12 months after learning the dyadic colour relationships. They chose the correct colour above chance at all three points in time, whereby performance was better in colour pairs at the beginning or end of the colour series. Nonetheless, they also performed above chance on internal colour pairs, which is indicative of long-term memory for quantitative differences in associative strength and/or for relational information. There were no indications for a decline in performance over time, indicating that geese may remember dyadic relationships for at least 6 months and probably well over 1 year. Furthermore, performance in the memory task was unrelated to the individuals’ sex and their performance while initially learning the dyadic colour relationships. We discuss possible functions of this long-term memory in the social domain. 相似文献
173.
Empirical studies have validated that basic needs satisfaction supported by video game play predicts motivation and engagement outcomes. However, few studies specifically manipulated game features for each of the three basic needs specified in the self-determination theory (SDT) to examine how the game features impact players' need satisfaction and game experience. The current study employed an in-house developed exergame and manipulated the game features in a 2 (autonomy-supportive game features: on vs. off) × 2 (competence-supportive game features: on vs. off) experiment to predict need satisfaction, game enjoyment, motivation for future play, effort for gameplay, self-efficacy for exercise using the game, likelihood of game recommendation, and game rating. The manipulated game features led to the corresponding need satisfaction. Manipulated autonomy-supportive and competence-supportive game features had main effects on most motivation and engagement outcomes. Need satisfaction of autonomy and need satisfaction of competence were both found to be mediators for the relationships between the game features and the motivation and engagement outcomes. The findings add evidence to support the underlying mechanism postulated by SDT for media enjoyment and motivation as well as the emerging entertainment research conceptualizing enjoyment as need satisfaction. The findings also have practical implications for intervention effort that intends to capitalize the motivational pull of video games. 相似文献
174.
This study examines the indirect effects of extensive negative political attack ads in the 2004 presidential election from a third-person effects perspective. Results of a survey using a probability sample of 496 college students indicate that these students believe attack ads harm others more than themselves. Moreover, the respondents tended to perceive attack ads in traditional media to have a greater harmful effect on self and others than attack ads on the Internet. Contingent factors that account for the magnitude of third-person effects include social distance and knowledge. Further, exposure to attack ads was found to be the strongest predictor of perceived harms of such ads on self and others, but only perceived harm on others is a significant predictor of support for restrictions on attack ads. The study contributes to research on the third-person effect by testing perceived harms of attack ads on self and others separately on likelihood to support restrictions. 相似文献
175.
This study was inspired by the rise in television targeting toddlers and preverbal infants (e.g., Teletubbies, Baby Mozart). Overall, we investigated if very young children who are in the early stages of language acquisition can learn vocabulary quickly (fast map) from television programs. Using a fast mapping paradigm, this study examined a group (n = 48) of toddlers (15–24 months) and their ability to learn novel words. Utilizing a repeated measures design, we compared children's ability to learn various novel words in 5 different conditions. These included the presentation and identification of a novel word by an adult speaker via live presentation when the toddler was attending (i.e., joint reference), an adult via live presentation when the toddler was not attending, an adult speaker on television, and an edited clip from a children's television program (Teletubbies). Overall, the toddlers were most successful in learning novel words in the joint reference condition. They were significantly less successful in the children's program condition. Furthermore, there was a significant interaction between age and condition on children's performance. Both younger (15–21 months) and older (22–24 months) participants identified the target objects when they were taught the novel word by an adult speaker; however, it appeared that children under the age of 22 months did not identify the target item when they were taught the novel word via the television program. 相似文献
176.
Increased alpha and theta activities in electroencephalography (EEG) have been found during various forms of meditation. However, advanced stage of meditation drew less attention to date. We aimed at exploring EEG characteristics during advanced meditation. Bilateral absolute alpha and theta EEG powers were recorded when a single meditator at rest, exercising breath meditation, and reaching the advanced meditative stage in 10 sessions of meditation. Averaged time-series data were analyzed using simulation modeling analysis to compare the powers during different meditative phases. During breath meditation, significantly higher activities compared with baseline were found only in bilateral theta (P = 0.0406, 0.0158 for left and right sides, respectively), but not in alpha (P = 0.1412, 0.0978 for left and right sides, respectively) bands. When meditation advanced, significantly increased activities were found both in bilateral alpha (P = 0.0218, 0.0258 for left and right sides, respectively) and theta (P = 0.0308, 0.0260 for left and right sides, respectively) bands compared against breath meditation. When advanced meditation compared against baseline, bilateral alpha (P = 0.0001, 0.0001 for left and right sides, respectively) and theta (P = 0.0001, 0.0001 for left and right sides, respectively) bands revealed significantly increased activities. Our findings support that internalized attention manifested as theta activity continuingly enhances significantly in sequential phases of meditation, while relaxation manifested as alpha activity is significant only after the advanced meditative phase is reached. 相似文献
177.
The present study aimed to investigate the psychological displacement paradigm in diary-writing (PDPD) had both immediate and short-term psychological benefits. Participants were randomly assigned to write about their recent negative life experiences two times a week for 2 weeks in PDPD group or comparison group. Results revealed that the PDPD group displayed a decrease in negative emotion and an increase in positive emotion immediately after each writing session; they also showed an increase in psychological well-being relative to the comparison group for at least 2 weeks. Implications for PDPD are discussed. 相似文献
178.
以肖邦音乐为刺激材料,采用数字n-back实验范式来研究肖邦音乐对工作记忆的影响方式,并通过运用事件相关电位技术(ERP技术),研究不同音乐条件下,正常人大脑皮层的脑电活动情况,进而探讨音乐对工作记忆影响的神经机制。30名被试参加了3种音乐条件(无音乐、先导音乐、背景音乐)下的n-back(n=1、2)工作记忆任务的行为实验,收集行为数据;14名被试参加了同样实验过程的ERP实验,记录脑电数据。行为结果发现音乐条件对工作记忆效果有显著影响,且先导音乐条件下记忆效果最好;脑电结果显示P3波幅随记忆负荷的增加呈下降趋势,高记忆负荷水平下,P3波幅随先导音乐、背景音乐、无音乐的顺序逐渐呈现下降趋势;源定位分析发现音乐对工作记忆的促进作用可能跟大脑顶叶被激活有关。 相似文献
179.
180.