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921.
Deficits in executive functions (EF) have been found in school-age children and adolescents with externalizing behavior disorders. Present meta-analysis was carried out to determine whether these EF impairments can also be found in preschool children with externalizing behavior problems. Twenty-two studies were included with a total of 4021 children. Four separate meta-analyses were conducted, concerning overall EF, working memory, inhibition and cognitive flexibility. A medium correlation effect size was obtained for overall EF (ESzr?=?0.22) and for inhibition (0.24), whereas a small effect size was found for working memory (0.17) and for cognitive flexibility (0.13). Moderator analyses revealed a stronger effect for older preschoolers compared to younger preschoolers, and for children from referred samples compared to community samples. These results show that EF, especially inhibition, is related to externalizing behavior problems already in preschool years.  相似文献   
922.
We surveyed well-acquainted dyads about two key moral character traits (Honesty–Humility, Guilt Proneness), as well as several other individual differences. We examined self-other agreement, similarity, assumed similarity, and similarity-free agreement (i.e., self-other agreement controlling for similarity and assumed similarity). Participants projected their own level of moral character onto their peers (i.e., moderately high assumed similarity), but were nonetheless able to judge moral character with reasonable accuracy (moderately high self-other agreement and similarity-free agreement), suggesting that moral character traits can be detected by well-acquainted others. Regardless of reporting method, Honesty–Humility and Guilt Proneness were correlated with delinquency, unethical decision making, and counterproductive work behavior, suggesting that unethical behavior is committed disproportionately by people with low levels of these character traits.  相似文献   
923.
924.
Attention is a complex domain that has reawakened research interest in recent years. There are relatively few studies that have examined age-related changes across different attention subcomponents, such as selection, maintenance, and control, using large samples covering a wide age range. The present study assessed performance in 466 participants in order to identify the ages at which mature performance was reached across differing attention subcomponents. Furthermore, we investigated whether the nature of the attentional demands or task difficulty predicted the age at which stable levels of performance were reached. The results supported the former rather than the latter alternative.  相似文献   
925.

We present the first report of icosahedral phase i-phase formation in rapidly quenched alloys of Ti Zr Co . Electron diffraction patterns of i TiZrCo 53 27 20 contain features, such as anisotropic spot shapes and arcs of diffuse scattering, that are characteristic of the disordered icosahedral phases found in Ti 3d transition metal Si O and Ti Zr Fe alloys. The features are less prominent than in those alloys, however, suggesting that this i-phase may have structural order intermediate between those strongly disordered i-phases and more ordered Ti Zr Ni i-phases, showing none of these features. The quasilattice constant for a i TiZrCo, 0 51 nm, is close to that of i TiZrNi . The i-phase in rapidly q quenched Ti Zr Co alloys is deeply metastable and transforms exothermically o to the hexagonal Laves phase about 500 C. The Laves phase transforms to the o T bcc solid solution phase b-Ti and the Ti Ni-type fcc structure for 630 C. A 2 reversible transformation between the b-Ti and the hexagonal solid solution phase a-Ti is observed on temperature cycling; the Ti Ni-type fcc phase is 2 stable over the entire temperature range.  相似文献   
926.
The diffusion and surface oxidation rates of Fe deposited on Si and barrier layers of Al/SiO2 and Al2O3/SiO2 have been comparatively studied and correlated with the growth of carbon nanotubes (CNTs). Initially, Fe/Si, Fe/Al/SiO2/Si and Fe/Al2O3/SiO2/Si samples were subjected to thermal chemical vapour deposition (CVD) at ~650°C for ~30?min to grow the CNTs. Scanning electron microscopy analysis showed that the height of the CNTs on the Fe/Al2O3/SiO2/Si samples was relatively high (~9.5–11?µm), as compared with the other samples. To investigate this, a few as-prepared samples were thermally annealed at ~650°C for ~30?min and characterized by dynamic secondary ion mass spectroscopy (D-SIMS) and X-ray photoelectron spectroscopy (XPS). The D-SIMS results showed that the diffusion depth, x Fe, and magnitude of the diffusivity, D Fe, of the Fe atoms are highest for the Fe/Si sample. This is attributed to vacancy-mediated migration, which leads to the formation of unstable, non-stoichiometric Fe–Si and Fe–O–Si phases. However, for the Fe/Al2O3/SiO2/Si samples, the magnitudes of x Fe and D Fe are found to be the lowest, which indicates steric hindrance to Fe by the Al2O3 layers. The XPS analysis revealed that the surface metallic state, after annealing, is almost unaffected for the Fe/Al2O3/SiO2/Si samples, whereas the majority of the Fe precipitate was observed to be oxidized in the case of the other samples.  相似文献   
927.
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale.  相似文献   
928.
The burden of HIV disease is concentrated in sub-Saharan Africa, particularly in South Africa (SA). Whilst there have been many studies conducted on the biomedical and socio-psychological aspects of HIV and AIDS, insufficient attention has been paid to the quality of life of those infected with the virus. The primary purpose of the study was to determine the predictors of quality of life enjoyment and satisfaction (Q-LES) among individuals infected with HIV. A battery of questionnaires, which included the Hospital Anxiety and Depression Scale (HADS) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), were administered to 121 participants. Data was analysed using SPSS. Of the total sample (n = 121), 74% were females. The study found that a large proportion (49.5%) of the sample within the age group 25–49 years old experienced psychological distress. Those who were not on antiretroviral treatment (ART) were significantly affected (66%). Psychological distress was significantly prevalent among HIV positive individuals and also the strongest predictor of Q-LES among these individuals.  相似文献   
929.
930.
Self-concepts change from context to context. The experience that one's self is context-sensitive may be universal, however the amount and meaning of context-sensitive self vary across cultures. Cross-cultural differences in the amount and meaning of context-sensitive self were investigated in three Western cultures (Australia, Germany, and UK) and two East Asian cultures (Japan and Korea). The amount of context-sensitivity of self was greater in Japan than in Western cultures and Korea. The meaning of context-sensitive self also varied across cultures. In the Western cultures, a context-invariant self was seen to be clear and true; however, these patterns were not observed in the East Asian cultures. In Korea, a context-invariant self was interpreted to be exhibiting a relational self, which adheres to the ethics of care. In Japan, it was a context-sensitive self that was seen to be true, implying that the true self in Japan may mean to be true to the self-in-context, rather than the transcendental, decontextualized self. The results suggest the importance of differentiating East Asian cultures such as Japan and Korea. The utility of quantitative methods in explicating cultural meaning was highlighted.  相似文献   
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