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61.
Allwein  Gerard  MacCaull  Wendy 《Studia Logica》2001,68(2):173-228
Gelfand quantales are complete unital quantales with an involution, *, satisfying the property that for any element a, if a b a for all b, then a a* a = a. A Hilbert-style axiom system is given for a propositional logic, called Gelfand Logic, which is sound and complete with respect to Gelfand quantales. A Kripke semantics is presented for which the soundness and completeness of Gelfand logic is shown. The completeness theorem relies on a Stone style representation theorem for complete lattices. A Rasiowa/Sikorski style semantic tableau system is also presented with the property that if all branches of a tableau are closed, then the formula in question is a theorem of Gelfand Logic. An open branch in a completed tableaux guarantees the existence of an Kripke model in which the formula is not valid; hence it is not a theorem of Gelfand Logic.  相似文献   
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Family and contextual predictors of depression in inner-city, African American youth have rarely been examined. In this study we explore the contribution of current and historical life events, family conflict, perceived social support from mother, maternal depression, and maternal explanatory style to the depressive symptoms of inner-city African American school-age (M = 10.7 years) children. Home interviews were conducted with 89 mother and child dyads living in moderate- to high-violent areas of a southeastern city. Regression analyses revealed that the children in this sample with higher levels of depressive symptoms had higher levels of child-reported everyday stress, were more likely to have been abused at some point in their past, came from homes with mothers who were less well educated, and had mothers who reported higher levels of depression, a past history of domestic abuse, as well as a less pessimistic explanatory style. Implications for interventions with inner-city African American families are discussed.  相似文献   
64.
Although research on the influence of neighborhoods on the development of youth is growing, few researchers have examined the impact of neighborhood quality on physiological outcomes or across gender. The present experiment examined gender differences in the association of neighborhood quality and cardiovascular reactivity (increased blood pressure, BP, in response to stress) among 77 healthy African American adolescents (46% male; M age = 14 years). Participants took part in a cold-face stimulus task to determine reactivity scores. After controlling for baseline BP, family income, and parental education, poorer neighborhood quality was associated with increases in both systolic and diastolic BP to the cold-face task for females, and decreases in BP for males. Adolescents’ reports of life stress and support from family members did not explain the differential effect of neighborhood quality across gender. Implications for future research are discussed.  相似文献   
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Socially promoted physical appearance ideals for women place increasing importance on muscularity, resulting in growing muscularity concerns among traditional college-age women. To date, however, instruments for assessing the type of muscularity concerns reported by women are lacking. The aim of the present study was therefore to develop such a scale and examine its psychometric properties among a sample of young women. Findings from an exploratory factor analysis (n = 235) and a confirmatory factor analysis (n = 130) revealed a two-factor structure, including a five-item Attitudes subscale (α = .89) and a five-item Behaviors subscale (α = .90), which were moderately correlated, r = .50. In addition, the scale demonstrated good 2-week test-retest reliability (r = .76), and the subscales revealed moderate-to-large associations with body image concerns, drive for thinness, and exercise engagement, indicating concurrent validity. Thus the new Female Muscularity Scale is a useful and promising tool for assessing muscularity concerns among young women, and it may help toward understanding the role of pressures to achieve a toned body in the development of body image, eating, and exercise disorders.  相似文献   
67.
Intelligence differences might contribute to true differences in personality traits. It is also possible that intelligence might contribute to differences in understanding and interpreting personality items. Previous studies have not distinguished clearly between these possibilities. Before it can be accepted that scale score differences actually reflect personality differences, personality items should show measurement invariance. The authors used item response theory to test measurement invariance in the five-factor model scales of the International Personality Item Pool (IPIP) and NEO-Five-Factor Inventory (NEO-FFI) across two groups of participants from the Lothian Birth Cohort 1936 with relatively low and high cognitive abilities. Each group consisted of 320 individuals, with equal numbers of men and women. The mean IQ difference of the groups was 21 points. It was found that the IPIP and NEO-FFI items were measurement invariant across all five scales, making it possible to conclude that any differences in IPIP and NEO-FFI scores between people with low and high cognitive abilities reflected personality trait differences.  相似文献   
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Despite the growth in children's purchasing power, surprisingly little is known about how children respond to sales promotions. We conduct two experiments to address this issue. Study 1 shows that elementary-aged (second and fifth grade) children's purchase decisions are influenced by the presence of sales. Study 2 demonstrates that both age groups favor conceptually easier promotions, even when the sale is inferior. Additionally, we find that children have difficulty applying mathematical concepts to sales promotions, regardless of classroom mastery of the associated operations. Together, these results indicate that elementary-aged children routinely incorporate sales into purchase decisions, sometimes with suboptimal results.  相似文献   
69.
Academic buoyancy refers to a positive, constructive, and adaptive response to the types of challenges and setbacks experienced in a typical and everyday academic setting. In this project we examined whether academic buoyancy explained any additional variance in test anxiety over and above that explained by coping. Two hundred and ninety-eight students in their final two years of compulsory schooling completed self-report measures of academic buoyancy, coping, and test anxiety. Results suggested that buoyancy was inversely related to test anxiety and unrelated to coping. With the exception of test-irrelevant thoughts, test anxiety was positively related to avoidance coping and social support. Test-irrelevant thoughts were inversely related to task focus, unrelated to social support, and positively related to avoidance. A hierarchical regression analysis showed that academic buoyancy explained a significant additional proportion of variance in test anxiety when the variance for coping had already been accounted for. These findings suggest that academic buoyancy can be considered as a distinct construct from that of adaptive coping.  相似文献   
70.
In addition to the potential for ongoing health concerns, adolescent and young adult (AYA) childhood cancer survivors frequently report posttraumatic stress symptoms (PTSS). The current study examines whether beliefs about health moderate the relationship between the number of health problems and PTSS 2 months later in 140 survivors. Beliefs, as measured by scales of the Health Competence Beliefs Inventory (HCBI), negatively related to PTSS while health problems positively related to PTSS. Three scales of the HCBI-health perceptions, satisfaction with healthcare and cognitive competence—were significant moderators. The relationship between health problems and PTSS was stronger in the presence of less adaptive beliefs. These beliefs represent potentially malleable intervention targets for reducing PTSS in childhood cancer survivors.  相似文献   
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