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211.
This article examines cultural differences in how people value future and past events. Throughout four studies, the authors found that European Canadians attached more monetary value to an event in the future than to an identical event in the past, whereas Chinese and Chinese Canadians placed more monetary value to a past event than to an identical future event. The authors also showed that temporal focus-thinking about the past or future-explained cultural influences on the temporal value asymmetry effect. Specifically, when induced to think about and focus on the future, Chinese valued the future more than the past, just like Euro-Canadians; when induced to think about and focus on the past, Euro-Canadians valued the past more than the future, just like Chinese. 相似文献
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213.
Non-amnestic mild cognitive impairment (naMCI) is one of the clinical subtypes of mild cognitive impairment (MCI). However, the characteristics of memory deficits in naMCI as assessed by clinical neuropsychological evaluations are not clear. In this study, a battery of neuropsychological tests was administered to 122 cognitively normal controls (NC), 133 amnestic mild cognitive impairment (aMCI) patients, and 72 naMCI patients. The results showed that in individuals with naMCI, episodic memory, and other cognitive domains were impaired. The Prospective Memory Test (PMT) event-based prospective memory (EBPM), the Symbol Digit Modalities Test (SDMT) Accidental Memory, Stick test (ST) visuoconstructional memory, and ST Working Memory were impaired, yet did not reach the level of aMCI. Semantic memory was affected to a degree comparable with aMCI. Some functions like Auditory Verbal Learning Test (AVLT) recognition, and Judgment of Confidence (JOC) were maintained, as well as PMT Time-Based Prospective Memory (TBPM). This study verified that memory impairment among individuals with naMCI was mainly in memory functions mediated by the frontotemporal cortex. 相似文献
214.
ABSTRACTThe basic mechanisms governing the process of cracking of single-layer brittle films have been extensively explored through both simulations and experiments. However, the role that an adhesive interlayer plays in the cracking of the overlying brittle film remains unclear. By performing three-point bending experiments, we observed that the insertion of a 100?nm thick Ti interlayer changed the cracking behaviour of TiN films from a continuous pattern to a discontinuous pattern. The slight change in the microstructure of the film and the increase in film thickness arising from the addition of the Ti interlayer are unlikely to cause the observed cracking morphology. The combination of the different interface between the Ti and the steel substrate and the fracture of the Ti interlayer are responsible for the transition in the TiN film cracking morphologies. 相似文献
215.
Titanium matrix composites reinforced by an in situ formed networking amorphous phase have been prepared directly in the form of as-cast ingots. The composites show significant compressive and tensile plasticity. In contrast to the highly localized plasticity for most monolithic amorphous alloys, the tensile deformation of the current composites distributes uniformly over the entire specimen as a consequence of substantial work (strain) hardening. The formation mechanism of the networking structure, as a result of well-separated two-step solidification of the current alloy melts, have possible implications for composite synthesis in other alloy systems. 相似文献
216.
A new stable icosahedral quasicrystal has been found in annealed Cd-Mg-Dy alloys. The composition of the icosahedral phase was determined to be approximately Cd66Mg21Dy13. Powder X-ray and electron diffraction patterns revealed that the phase has a primitive icosahedral lattice with a quasilattice parameter aR = 0.5634 nm. The electron diffraction study confirmed that the phase has a well ordered primitive icosahedral structure. 相似文献
217.
篇章形式的阅读测验是一种典型的题组测验,在进行项目功能差异(DIF)检验时需要采用与之匹配的DIF检验方法.基于题组反应模型的DIF检验方法是真正能够处理题组效应的DIF检验方法,能够提供题组中每个项目的DIF效应测量,是题组DIF检验方法中较有理论优势的一种,主要使用的方法是Rasch题组DIF检验方法.该研究将Rasch题组DIF检验方法引入篇章阅读测验的DIF检验中,对某阅读成就测验进行题组DIF检验,结果显示,该测验在内容维度和能力维度的部分子维度上出现了具有显著DIF效应的项目,研究从测验公平的角度对该测验的进一步修改及编制提出了一定的建议.研究中进一步将Rasch题组DIF检验方法与基于传统Rasch模型的DIF检验方法以及变通的题组DIF检验方法的结果进行比较,研究结果体现了进行题组DIF检验的必要性与优越性.研究结果表明,在篇章阅读测验中,能够真正处理题组效应的题组DIF检验方法更加具有理论优势且对于阅读测验的编制与质量的提高具有更重要的意义. 相似文献
218.
Mixture factor analysis is examined as a means of flexibly estimating nonnormally distributed continuous latent factors in the presence of both continuous and dichotomous observed variables. A simulation study compares mixture factor analysis with normal maximum likelihood (ML) latent factor modeling. Different results emerge for continuous versus dichotomous outcomes. For dichotomous outcomes, normal ML path estimates have bias that worsens as latent factor skew/kurtosis increases and does not diminish as sample size increases, whereas the mixture factor analysis model produces nearly unbiased estimators as sample sizes increase (500 and greater) and offers near nominal coverage probability. For continuous outcome variables, both methods produce factor loading estimates with minimal bias regardless of latent factor skew, but the mixture factor analysis is more efficient. The method is demonstrated using data motivated by a study on youth with cystic fibrosis examining predictors of treatment adherence. In summary, mixture factor analysis provides improvements over normal ML estimation in the presence of skewed/kurtotic latent factors, but due to variability in the estimator relating the latent factor to dichotomous outcomes and computational issues, the improvements were only fully realized, in this study, at larger sample sizes (500 and greater). 相似文献
219.
Xiuyan Guo Nan Zhao Si Wang Weilin Chen Rong Gong Baihua Xu 《The Journal of general psychology》2013,140(2):210-224
Risk preference during decision making depends not only on the potential risk and profits but also on the roles taken in the current task. Those who perform tasks are more risk-seeking than those who only watch. Given the prominent effect of experiencing the task, the player–spectator discrepancies are supposed to arise in the experiencing phase instead of the choosing phase. In the present study, the authors separated the experiencing role and the choosing role through a stylus maze task in which participants first performed in pairs—one as the player and the other as the spectator—and then chose from two rewarding options for themselves or their partners. The findings show that the experience as players induced a risk-seeking tendency in decision making, which suggests that it was the experiencing role, rather than the choosing role, that caused the difference of risk preference, at least for financially motivated groups and under similar task conditions. 相似文献
220.