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111.
Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]MgO~2° from (0?0?0?1)α-Mg and (0?1?1)MgO?//[2?1?1?0)α-Mg; and OR II: (1?1?1)MgO//(1?1?0?1)α-Mg and [0?1?1]MgO//[1?2?1?1]α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion. 相似文献
112.
Negative information processing biases have been hypothesised to serve as precursors for the development of depression. The current study examined negative self-referent information processing and depressive symptoms in a community sample of adolescents (N = 291, Mage at baseline = 12.34 ± 0.61, 53% female, 47.4% African-American, 49.5% Caucasian and 3.1% Biracial). Participants completed a computerised self-referent encoding task (SRET) and a measure of depressive symptoms at baseline and completed an additional measure of depressive symptoms nine months later. Several negative information processing biases on the SRET were associated with concurrent depressive symptoms and predicted increases in depressive symptoms at follow-up. Findings partially support the hypothesis that negative information processing biases are associated with depressive symptoms in a nonclinical sample of adolescents, and provide preliminary evidence that these biases prospectively predict increases in depressive symptoms. 相似文献
113.
Sophie Lebel Ada Y. M. Payne Kenneth Mah Jonathan Irish Gary Rodin Gerald M. Devins 《Psychology, health & medicine》2016,21(5):583-592
Stigma appears to influence emotional distress and well-being in cancer survivors, but cross-cultural differences have been ignored. Previous studies suggest that stigma may be especially relevant for survivors of Asian origin. However, their study designs (e.g. focused on female cancers, qualitative designs, and an absence of comparison groups) limit the strength of this conclusion. We hypothesized that (1) Asian-born Chinese immigrants (AI) would report more perceived cancer-related stigma than Western-born Caucasians (WBC); and (2) the impact of stigma on emotional distress and well-being would be greater in AI as compared to WBC. Head and neck cancer survivors (n = 118 AI and n = 404 WBC) completed measures of well-being, emotional distress, and a three-item indicator of stigma in structured interviews. The majority of respondents (59%) reported one or more indicators of stigma. Stigma correlated significantly with emotional distress (r = .13, p = .004) and well-being (r = ?.09, p = .032). Contrary to our hypotheses, WBCs and AIs did not differ in reported stigma nor did we detect differences in its psychosocial impact. Stigma exerts a deleterious psychosocial impact on head and neck cancer survivors. It did not differ significantly between AI and WBC survivors. 相似文献
114.
Fifty-eight male and 66 female junior high school students were examined to determine their preferences for sex of counselor under personal/social and educational hypothetical counseling situations. Girls demonstrated a definite same-sex preference for both counseling situations, while boys preferred male counselors for personal/social counseling and had opposite-sex preferences for educational counseling. Implications of the findings are discussed in light of earlier contradictory results from research on college students. 相似文献
115.
In this study we investigated C. Gilligan's [(1982), In a different voice: Psychological theory and women's development, Cambridge, Massachusetts: Harvard University Press] suggestion that women and men, due to socialization, develop differently in terms of moral development [L. Kohlberg (1969), “Stage and Consequence: The Cognitive Development Approach to Socialization,” In D. G. Goslin (Ed.), Handbook of socialization: Theory and research, Chicago: Rand McNally]. We also considered whether men and women differ in terms of a related construct, values of equity and equality [K. A. Rasinski (1987), “What's Fair Is Fair or Is It? Value Differences Underlying Public Views About Social Justice,” Journal of Personality and Social Psychology, Vol. 53, pp. 201–211]. It is our expectation that gender influences overall orientation in terms of the two sets of values, and that differences in values lead decision makers to weigh decision issues and to make final decisions differently. Results suggest that there are some gender-related differences in value systems, weights of decision issues, and final decisions. 相似文献
116.
Judgment strategies of 169 undergraduate students on problems to judge the contingency between two binary events were identified by the method of rule-based analysis to clarify whether or not the strategies the subjects used would be affected by the concrete nature of the contingency table. Problems were constructed along two factors: total cell frequency and width of range of objective contingencies. Although the factor of total cell frequency had no effect on subjects' strategies, the number of subjects who changed strategies corresponding with problem instances increased when the objective contingencies were set closer to zero or when problems became more difficult. These results are discussed in the context of previous studies of this issue in the literature. 相似文献
117.
Effective computer skill training is vital to organizational productivity. Two experiments (N = 288) demonstrated that the behavior modeling approach to computer skill training could be substantially improved by incorporating symbolic mental rehearsal (SMR). SMR is a specific form of mental rehearsal that establishes a cognitive link between visual images and symbolic memory codes. As theorized, the significant effects of SMR on declarative knowledge and task performance were shown to be fully mediated by changes in trainees' knowledge structures. The mediational role of knowledge structures is expected to generalize to other training interventions and cognitive skill domains. Our findings have the immediate implications that practitioners should use SMR for improving the effectiveness of computer skill training. 相似文献
118.
Maureen E. Kenny Lynn Y. Walsh-Blair Janine Bempechat 《Journal of Vocational Behavior》2010,77(2):205-212
Drawing upon expectancy value, hope, and self-determination theories, this study explores the contributions of work-based beliefs and autonomy support as predictors of adaptive achievement-related beliefs. Two hundred and one urban high school students who were enrolled in a work-based learning program completed measures of work hope, autonomy support, and achievement beliefs. Results from the full canonical correlation model revealed that work hope, career planning, and autonomy support shared 37.5% of the variance with achievement-related beliefs. Moreover, work hope and teacher autonomy support further contributed unique variance in explaining these beliefs. The findings contribute to the theoretical knowledge base concerning the value of work-based learning in fostering academic motivation among adolescents. 相似文献
119.
Y. Joel Wong Kimberly K. Tran Andre Lai 《Journal of multicultural counseling and development》2009,37(2):105-116
Using a computer‐based text analysis of 218 Asian Americans' writing samples, the authors found that enculturation as well as use of negative emotion and positive emotion words were associated with depressive symptoms. Enculturation was also found to moderate the relation between use of negative emotion words and cognitive‐affective depressive symptoms. Utilizando un análisis de texto computerizado de muestras escritas por 218 individuos Asiático‐americanos, los autores hallaron que la asimilación cultural y el uso de palabras de emoción positivas y negativas están asociadas con síntomas depresivos. También se halló que la asimilación cultural modera la relación entre el uso de palabras de emoción negativas y los síntomas depresivos cognitivo‐afectivos. 相似文献
120.
Human conscious awareness is commonly seen as the climax of evolution. However, what function-if any-it serves in human behavior is still debated. One of the leading suggestions is that the cardinal function of conscious awareness is to integrate numerous inputs-including the multitude of features and objects in a complex scene-across different levels of analysis into a unified, coherent, and meaningful perceptual experience. Here we demonstrate, however, that integration of objects with their background scenes can be achieved without awareness of either. We used a binocular rivalry technique known as continuous flash suppression to induce perceptual suppression in a group of human observers. Complex scenes that included incongruent objects escaped perceptual suppression faster than normal scenes did. We conclude that visual awareness is not needed for object-background integration or for processing the likelihood of an object to appear within a given semantic context, but may be needed for dealing with novel situations. 相似文献