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101.
102.

We have found stable icosahedral (i) phases in alloys with nominal compositions around Al 72 Pd 17 Ru 11 and Al 72 Pd 17 Os 11 . They display very sharp X-ray diffraction peaks, indicating high structural order as in other Al-based i-phases such as i-(Al-Pd-TM) (transition metal TM = Mn or Re) and i-(Al-Cu-TM) (TM =Fe, Ru or Os). The i phases are formed via peritectic reaction and, upon heating, they transform into a mixture of a liquid and the 1/0 cubic approximant phase. The electrical resistivity of the i phases was measured in a wide temperature range from 14K to above their melting points and a reversible change of the resistivity across the melting point has been observed in situ for the first time.  相似文献   
103.
The atomistic structure of the 3C-SiC/Si(001) interface has been investigated using a combination of aberration-corrected transmission electron microscopy and a newly developed image processing method for eliminating artificial contrast. The structures having periods four times longer than those of the silicon lattice have been observed distinctly in images taken along both Si[110] and Si[100] directions. Contrary to theoretical models proposed previously, the interface of the three-dimensional structural model that we constructed on the basis of our experiments has a silicon-rich configuration. We have clarified that the strain field induced by the two-dimensional misfit between Si(001)-(4?×?4) and SiC(001)-(5?×?5) is relaxed by the two-dimensional network of misfit dislocations; simple edge dislocations with [100] and [010] directions and Lomer dislocations with [110] and [110] directions. The atomistic structures of the Lomer dislocations have been also clarified.  相似文献   
104.
ABSTRACT

What three words come to your mind in response to “happiness”? Using a free-association task [cf. Nelson, D. L., McEvoy, C. L., & Dennis, S. (2000). What is free association and what does it measure? Memory and Cognition, 28, 887–899], this research finds that the number of social words (e.g. family, love) provided in link to happiness predicts people’s actual life satisfaction level. However, this association was significantly moderated by the person’s self-perceived financial state. The contingency between holding a socially-oriented belief about happiness and experienced life satisfaction was significant among members of low socioeconomic status (SES), but not among the high SES group. This pattern was replicated across two divergent samples (Asian college students, Study 1; American adults, Study 2), regardless of one’s extraversion level (Studies 1, 2) and availability of social support (number of friends, Study 2). Given the overlapping function of money and social relationships (instrumental in promoting survival), believing in the social nature of happiness seems to be more central in the life satisfaction of those with less financial resource.  相似文献   
105.
This exploratory study examined the relationships between Africentric values, racial/ethnic identity, neighborhood satisfaction, and academic self‐efficacy beliefs among 88 African American elementary school children. Results indicated that Africentric values and neighborhood satisfaction were both predictive of academic self‐efficacy beliefs. Racial/ethnic identity did not significantly predict the outcome variable. Este estudio exploratorio examinó las relaciones entre valores Afrocéntricos, identidad racial/étnica, satisfacción en el vecindario y convicciones sobre la autoeficacia académica entre 88 niños Afroamericanos en la escuela elemental. Los resultados indicaron que tanto los valores Afrocéntricos como la satisfacción en el vecindario podían predecir las convicciones sobre autoeficacia académica. La identidad racial/étnica no predijo significativamente la variable del resultado.  相似文献   
106.
Although the rapid development of information technology has led to the increasing use of computer‐mediated communication (CMC), few studies have examined the relational aspect of mixed‐mode groups that use both face‐to‐face (FTF) communication and CMC. A field study comprising 42 student groups was conducted to assess the relationships among communication time, cohesion, and performance in mixed‐mode groups. The findings suggest that time spent in FTF communication significantly predicted group social cohesion, but time spent in CMC did not. In contrast, group task cohesion was predicted by time spent in CMC but not by time spent in FTF communication. Time spent in CMC was also a strong predictor of group task performance. These results suggest that FTF communication contributes to the social aspect of mixed‐mode groups and that CMC is beneficial to their task‐related aspect. The findings of mediation analyses showed a significant indirect effect among time spent in FTF communication, group social cohesion, and group contextual performance. In other words, time spent in FTF communication had a positive effect on group social cohesion, which in turn positively affected group contextual performance. However, no mediating effect was found among time spent in CMC, group task cohesion, and group task performance. Theoretical and practical implications of these findings are discussed.  相似文献   
107.
Previous research has suggested that biased attention toward emotional (typically threatening) stimuli contributes to ill-being (e.g., high levels of anxiety), but its contribution to well-being is less clear. The researchers assessed naturalistic shifts in attentional bias toward threatening and pleasant schematic face cues in response to five induced mood states in college students. They also assessed state anxiety and satisfaction with life concurrently and 3 weeks later. Controlling for concurrent anxiety, a fear-induced shift in attention to threatening cues was associated with increased levels of later anxiety. Controlling for concurrent life satisfaction, a happiness-induced shift in attention to emotional cues (both threatening and pleasant) was associated with increased levels of later life satisfaction. These results suggest that mood-induced changes in deployment of attention to emotional information may accumulate in ways that impact psychological functioning, yet these effects depend on mood state and the emotional cues afforded by the context.  相似文献   
108.
The objective of this article is to fully understand Internet addiction, we aimed to compare the attachment styles and psychopathologies associated with problematic Internet use with those related to alcohol use. Through the participation of 141 male participants, the present study assessed problematic Internet and alcohol use, attachment, psychopathology, and demographic data via the use of self-rating questionnaires. We explored the significant predictors among avoidant and anxious attachments, depression, anxiety, and phobia to explain problematic Internet and alcohol use. The results showed that anxious attachment, depression, and anxiety could explain problematic alcohol use. In contrast, both anxious and avoidant attachment as well as depression and phobia explained problematic Internet use. Additionally, depression moderated the effects of avoidant attachment on problematic Internet use. We demonstrated that the interaction of attachment and psychopathology predicts problematic Internet use originating from an earlier stage of life than that associated with problematic alcohol use.  相似文献   
109.
Cyclophosphamide (CYP) is an anti-neoplastic agent as well as an immunosuppressive agent. In order to elucidate the alteration in adult hippocampal function following acute CYP treatment, hippocampus-related behavioral dysfunction and changes in adult hippocampal neurogenesis in CYP-treated (intraperitoneally, 40 mg/kg) mice (8–10-week-old ICR) were analyzed using hippocampus-dependent learning and memory tasks (passive avoidance and object recognition memory test) and immunohistochemical markers of neurogenesis (Ki-67 and doublecortin (DCX)). Compared to the vehicle-treated controls, mice trained at 12 h after CYP injection showed significant memory deficits in passive avoidance and the object recognition memory test. The number of Ki-67- and DCX-positive cells began to decrease significantly at 12 h post-injection, reaching the lowest level at 24 h after CYP injection; however, this reverted gradually to the vehicle-treated control level between 2 and 10 days. We suggest that the administration of a chemotherapeutic agent in adult mice interrupts hippocampal functions, including learning and memory, possibly through the suppression of hippocampal neurogenesis.  相似文献   
110.
This study investigated the states-of-mind model of depression, anxiety, anger, life satisfaction and happiness in four ways. Three hundred and ninety-eight undergraduate students from Singapore participated in this study. First, states-of-mind ratio and positive automatic thoughts were positively correlated with life satisfaction and happiness, and negatively correlated with anxiety, depression, and anger. In contrast, negative automatic thoughts were positively correlated with anxiety, depression, and anger, and negatively correlated with life satisfaction and happiness. Second, the BSOM categories based depression-related automatic thoughts was able to significantly differentiate among levels of depression, happiness, life satisfaction, anxiety, and anger in ANOVA and in terms of variance accounted for as indicated by partial Eta squared. Third, the BSOM ratio was the best predictor for happiness and life satisfaction and second best predictor for depression, anxiety, and anger in terms of variance accounted for as indicated by adjusted R2, in comparison to the negative cognition model and positive cognition model. Fourth, both ANOVA results and multiple regression results showed that there is cognitive content-specificity for the BSOM based on depression-related automatic thoughts. Implications and limitations of these findings were discussed.  相似文献   
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