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151.
Studies examining within-person level self-efficacy effects on effort allocation have produced mixed results, ranging from positive, to null, to negative. Drawing on individual differences literature, we propose that the within-person relationship between self-efficacy and effort allocation depends on Conscientiousness, a personality trait reflecting the will to achieve and capacity to self-discipline. Individuals with higher levels of Conscientiousness will respond to lower self-efficacy with increased effort, resulting in an inverse relationship between self-efficacy and effort expenditure. In contrast, individuals with lower levels of Conscientiousness will need higher self-efficacy to stay task focused and sustain effort allocation, leading to a positive effect of self-efficacy on effort expenditure. Findings from a 3-week daily diary study generally support the hypothesized moderating effects of Conscientiousness. Theoretical and practical implications are discussed.  相似文献   
152.
We report that <c+a> pyramidal slipping could be more easily activated in textured Mg–Ca alloys with increasing Ca contents dissolved in α-Mg matrix under tensile deformation, and it is proposed that the decreased stacking fault energy plays the critical rule. In contrast, only twins and <a> basal dislocations are observed in the compressed samples. The results would provide insight into understanding of the deformation mechanism and designing more ductile Mg alloys.  相似文献   
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Although conspiracy theories are ubiquitous across times and cultures, research has not investigated how cultural dimensions may predict conspiracy beliefs. The present research examined intergroup conspiracy beliefs in United States and Chinese samples at the peak of the trade war. In two studies (one pre-registered; total N = 1,092), we asked US participants to what extent they believed Chinese institutions and companies were conspiring against the United states and Chinese participants to what extent they believed US institutions and companies were conspiring against China. Results revealed that such beliefs were stronger among Chinese than US participants due to higher power distance values and vertical collectivism. In particular, these cultural dimensions were associated with increased psychological involvement in intergroup conflict (as reflected by higher levels of collective narcissism and perceived outgroup threat), which in turn predicted intergroup conspiracy beliefs. Exploratory analyses suggested that particularly power distance values mediate these effects. We conclude that cultural dimensions that promote hierarchy in society are associated with increased intergroup conspiracy beliefs.  相似文献   
156.

With the rapid development of Internet techniques in China, more and more Chinese middle-aged and older adults have begun to use the Internet for their daily social interactions, and the resulting online social capital may affect their health. Using data from the Chinese General Social Survey of 2017 (n = 7733, aged 45–90 years old), this study investigated the influence of online social capital on the health of middle-aged and older adults in China, and the Heckman sample selection model was used to address potential sample selection bias in Internet use. The results show that number of online contacts significantly improved the physical health of middle-aged and older adults, while the level of depression was significantly reduced by online closeness of non-specific relationships, but more online interactions may slightly increase their depression. Furthermore, more online contacts were associated with elevated physical health among male, rural, less-educated and middle-aged adults, while more online closeness of non-specific relationships was associated with less depression in almost all subgroups. Online social capital can improve the health of middle-aged and older adults in China, so we should help increase older adults’ access to the Internet and improve their Internet skills to give full play to the positive health effect of online social capital. However, it should be alert to the negative health consequences caused by excessive Internet use.

  相似文献   
157.
We longitudinally investigated parental language context and infants' language experiences in relation to Dominican American and Mexican American infants' vocabularies. Mothers provided information on parental language context, comprising measures of parents' language background (i.e., childhood language) and current language use during interviews at infants' birth. Infants' language experiences were measured at ages 14 months and 2 years through mothers' reports of mothers' and fathers' engagement in English and Spanish literacy activities with infants and mothers' English and Spanish utterances during videotaped mother-infant interactions. Infants' vocabulary development at 14 months and 2 years was examined using standardized vocabulary checklists in English and Spanish. Both parental language context and infants' language experiences predicted infants' vocabularies in each language at both ages. Furthermore, language experiences mediated associations between parental language context and infants' vocabularies. However, the specific mediation mechanisms varied by language.  相似文献   
158.
The effects of irradiation on twin boundary migration in BCC Fe are studied by atomistic simulations. It is found that under the applied shear strain–stress, thermal spikes may create twinning dislocation loops (TDLs) at twin boundaries, so triggering twinning. Irradiation-generated clusters of point defect at twin boundaries may act as sources to nucleate TDLs. When a vacancy loop intersects with a twin boundary, the critical stress to activate a TDL is less than half of that required for a defect-free twin boundary.  相似文献   
159.
Using a combination of atomic-resolution high-angle annular dark-field (HAADF) Z-contrast imaging and ab initio calculations, atomic models of clusters 2 nm in diameter and 0.8 nm in height are proposed for the Al–Co–Ni pentagonal quasicrystal. This quasicrystal has 5-fold symmetry (the so-called 5f state) without superstructures, and is one of numerous modifications of the Al–Co–Ni decagonal quasicrystal. HAADF results reveal that the two-dimensional quasi-periodic lattice contains mainly Penrose pentagonal tiling. The centres within the decorated pentagonal tiles, i.e. the so-called pentagonal super-clusters, show structural characteristics having both a satellite-orbit shape and a pentagon-symmetry shape. The proposed atomic models, based directly on the HAADF images, are subjected to ab initio total energy calculations. After relaxation, the calculations demonstrate that the models with 5-fold symmetry are energetically more favourable than those with 10-fold symmetry.  相似文献   
160.
This paper presents a study of the deformation behaviour of a glassy phase in two Zr-based alloys, Zr65Ni10Cu5Al7.5Pd12.5 and Zr65Al7.5Ni10Pd17.5, performed in situ in a transmission electron microscope. In contrast to the case of shear localisation and formation of 10–20 nm thick shear bands in deformed bulk glassy samples studied earlier, it is found that in thin (electron-transparent) samples the glassy phase in front of a crack deforms more homogeneously and no nanocrystallisation takes place. The reasons for such behaviour are discussed. According to the observed results, one can conclude that the studied metallic glasses can be intrinsically ductile in submicrometre-sized volumes.  相似文献   
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