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261.
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
262.
Chunxiao Li C.K. John Wang Do Young Pyun Ying Hwa Kee 《Psychology of sport and exercise》2013,14(5):692-700
ObjectivesThe present study is a review on studies about the relationships between the three basic psychological needs/motivational regulations (i.e., amotivation, controlled regulation, extrinsic autonomous regulation, and intrinsic motivation) and burnout.DesignA systematic review and meta-analysis.MethodStudies were identified through five electronic databases and manual search using combinations of three groups of keywords. Three inclusion criteria were then used to screen the searched articles.ResultsEighteen studies met the inclusion criteria and these studies varied considerably in terms of their study characteristics (e.g., characteristics of participants, study designs, and outcome measures). The results also showed that the three basic psychological needs, intrinsic motivation, extrinsic autonomous regulation, and amotivation had small to large effects on predicting global burnout and its three dimensions. However, controlled regulation showed no or weak correlations with the burnout subscales.ConclusionsSelf-determination theory was generally supported in explaining athlete burnout. 相似文献
263.
Xufeng Liu Yang Liao Luping Zhou Gang Sun Min Li Lun Zhao 《Cognitive, affective & behavioral neuroscience》2013,13(3):491-500
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component. 相似文献
264.
It was recently demonstrated that detecting target objects (e.g., animals) in natural scenes can be done in a dual-task paradigm, in the near absence of spatial attention. Under the same conditions, subjects were unable to perform apparently simpler tasks involving synthetic stimuli (e.g., discriminating randomly rotated Ts and Ls, or a bisected colour disc and its mirror image). Classical theories predict that attention is more critical for the recognition of complex stimuli that cannot be easily separated on a single feature dimension. Therefore, these puzzling results have raised a number of questions. If it is not the complexity of a stimulus, what then determines the recognition task's attentional requirements? How does this differ between natural and artificial stimuli? What can these observations tell us about the mechanism of natural scene processing as well as its relation to attention? Here we show that removing colour information, or doubling the amount of information to be analysed, failed to make the natural scene categorization tasks significantly more “attention demanding”. Conversely, increasing discriminability or predictability did not diminish the need for attention in the case of synthetic stimuli. However, when the familiar letters, such as Ts or Ls, were presented upright, full attention was no longer required for discrimination. This suggests that familiarity and meaningfulness might be among the factors that determine attentional requirements for both natural and synthetic stimuli. 相似文献
265.
Mental rotation, as a covert simulation of motor rotation, could benefit from spatial updating of object representations. We are interested in what kind of visual cue could trigger spatial updating. Three experiments were conducted to examine the effect of dynamic and static orientation cues on mental rotation, using a sequential matching task with three-dimensional novel objects presented in different views. Experiment 1 showed that a rotating orientation cue with constant speed reduced viewpoint costs in mental rotation. Experiment 2 extended this effect with a varied-speed rotating orientation cue. However, no such benefit was observed with a static orientation cue in Experiment 3. These findings indicated that a visually continuous orientation cue is sufficient to elicit spatial updating in mental rotation. Furthermore, there may be differences in the underlying mechanisms of spatial updating on the basis of constant-speed rotating cues and varied-speed rotating cues. 相似文献
266.
Jinmian Yang Nan Li Suiping Wang Timothy J. Slattery Keith Rayner 《Visual cognition》2013,21(2):193-213
Previous studies have shown that a plausible preview word can facilitate the processing of a target word as compared to an implausible preview word (a plausibility preview benefit effect) when reading Chinese (Yang, Wang, Tong, & Rayner, 2012; Yang, 2013). Regarding the nature of this effect, it is possible that readers processed the meaning of the plausible preview word and did not actually encode the target word (given that the parafoveal preview word lies close to the fovea). The current experiment examined this possibility with three conditions wherein readers received a preview of a target word that was either (1) identical to the target word (identical preview), (2) a plausible continuation of the pre-target text, but the post-target text in the sentence was incompatible with it (initially plausible preview), or (3) not a plausible continuation of the pre-target text, nor compatible with the post-target text (implausible preview). Gaze durations on target words were longer in the initially plausible condition than the identical condition. Overall, the results showed a typical preview benefit, but also implied that readers did not encode the initially plausible preview. Also, a plausibility preview benefit was replicated: gaze durations were longer with implausible previews than the initially plausible ones. Furthermore, late eye movement measures did not reveal differences between the initially plausible and the implausible preview conditions, which argues against the possibility of misreading the plausible preview word as the target word. In sum, these results suggest that a plausible preview word provides benefit in processing the target word as compared to an implausible preview word, and this benefit is only present in early but not late eye movement measures. 相似文献
267.
Adults increase the certainty of their inductive inferences by observing more diverse instances. However, most young children fail to do so. The present study tested the hypothesis that children's sensitivity to instance diversity is determined by three variables: ability to discriminate among instances (Discrimination); an intuition that large numbers of instances increase the strength of conclusion (Monotonicity); ability to detect subcategories and evaluate numerical differences between the subcategories, or Extraction. A total of 219 Chinese children aged 6 to 11 were tested for sensitivity to diversity by means of Discrimination, Monotonicity, and Extraction. The results indicated that children at all ages were able to discriminate instances and attend to set size. However, only 9- and 11-year-olds demonstrated Extraction and sensitivity to diversity. Furthermore, among all children diversity scores increased linearly with the level of Extraction. These results suggest that the law of large numbers plays a role in children's diversity-based reasoning. 相似文献
268.
Shu Li 《Thinking & reasoning》2013,19(2):129-143
Two critical thinking skills—the tendency to avoid myside bias and to avoid one-sided thinking—were examined in three different experiments involving over 1200 participants and across two different paradigms. Robust indications of myside bias were observed in all three experiments. Participants gave higher evaluations to arguments that supported their opinions than those that refuted their prior positions. Likewise, substantial one-side bias was observed—participants were more likely to prefer a one-sided to a balanced argument. There was substantial variation in both types of bias, but we failed to find that participants of higher cognitive ability displayed less myside bias or less one-side bias. Although cognitive ability failed to associate with the magnitude of the myside bias, the strength and content of the prior opinion did predict the degree of myside bias shown. Our results indicate that cognitive ability—as defined by traditional psychometric indicators—turns out to be surprisingly independent of two of the most important critical thinking tendencies discussed in the literature. 相似文献
269.
Karen Z. H. Li Mervin Blair Virginia S. M. Chow 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(3):270-295
ABSTRACT Two experiments were conducted to examine possible sources of age-related decline in sequential performance: age differences in sequence representation, retrieval of sequence elements, and efficiency of inhibitory processes. Healthy young and older participants learned a sequence of eight animal drawings in fixed order, then monitored for these targets within trials of mis-ordered stimuli, responding only when targets were shown in the correct order. Responses were slower for odd numbered targets, suggesting that participants spontaneously organized the sequence in two-element chunks. Perseverations (responses to previously relevant targets) served as an index of inhibitory inefficiency. Efficiency of chunk retrieval and self-inhibition were lower for older than for younger adults. Increasing environmental support in Experiment 2 through overt articulation of current chunk elements showed a pattern of results similar to Experiment 1, with particular benefit for older adults. The findings suggest an underlying susceptibility to interference in old age. 相似文献
270.
Steven Paul Woods Michael Weinborn Yanqi Ryan Li Erica Hodgson Amanda R.J. Ng Romola S. Bucks 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(6):679-692
Older adults commonly experience declines in prospective memory, which describes one’s ability to “remember to remember,” and can adversely affect instrumental activities of daily living and healthcare compliance. However, the extent to which prospective memory failures may influence quality of life in typically aging older adults is not well understood. One-hundred and four community-dwelling older Australians (aged 50 to 82 years) were administered a comprehensive, neuropsychological battery that included the Memory for Intentions Screening Test (MIST), Prospective and Retrospective Memory Questionnaire (PRMQ), Instrumental Activities of Daily Living Questionnaire (IADLQ), and World Health Organization Quality of Life-8 (WHOQOL-8). Multiple regressions controlling for negative affect, medical comorbidities, and other neurocognitive functions revealed an interaction between prospective memory and instrumental activities of daily living in the concurrent prediction of quality of life. Among the 39 older adults who reported multiple problems on the IADLQ, lower performance-based prospective memory (MIST) and higher self-reported prospective memory failures in daily life (PRMQ) were significantly associated with lower quality of life (WHOQOL-8). Conversely, no significant associations were observed between prospective memory and quality of life in the 65 participants without IADL problems. Prospective memory difficulties adversely impact quality of life in community-dwelling older adults who experience problems independently managing their instrumental activities of daily living. These findings extend prior literature showing that prospective memory plays a unique role in the real-world outcomes of older adults and clinical populations and highlight the need to develop effective strategies to enhance prospective memory functioning in these vulnerable groups. 相似文献