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991.
Chassin Laurie; Dmitrieva Julia; Modecki Kathryn; Steinberg Laurence; Cauffman Elizabeth; Piquero Alex R.; Knight George P.; Losoya Sandra H. 《Canadian Metallurgical Quarterly》2010,24(1):48
Multiple theories suggest mechanisms by which the use of alcohol and drugs during adolescence could dampen growth in psychosocial maturity. However, scant empirical evidence exists to support this proposition. The current study tested whether alcohol and marijuana use predicted suppressed growth in psychosocial maturity among a sample of male serious juvenile offenders (n = 1,170) who were followed from ages 15 to 21 years. Alcohol and marijuana use prospectively predicted lower maturity 6 months later. Moreover, boys with the greatest increases in marijuana use showed the smallest increases in psychosocial maturity. Finally, heterogeneity in the form of age-related alcohol and marijuana trajectories was related to growth in maturity, such that only boys who decreased their alcohol and marijuana use significantly increased in psychosocial maturity. Taken together, these findings suggest that patterns of elevated alcohol and marijuana use in adolescence may suppress age-typical growth in psychosocial maturity from adolescence to young adulthood, but that effects are not necessarily permanent, because decreasing use is associated with increases in maturity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Rausch Sarah M.; Gramling Sandra E.; Auerbach Stephen M. 《Canadian Metallurgical Quarterly》2006,13(3):273
Three hundred eighty-seven undergraduate students in a large-group setting were exposed to 20 min of either meditation, progressive muscle relaxation (PMR), or a control condition, followed by 1 min of stress induction and another 10 min of each intervention. Participants in the meditation and PMR groups decreased more in cognitive, somatic, and general state anxiety than controls. The PMR group had the greatest decline in somatic anxiety, lending some support to the cognitive/somatic specificity hypothesis. After exposure to a visual stressor, those in the relaxation conditions had higher levels of anxiety and recovered more quickly than controls. Findings demonstrated the effectiveness of brief group training in meditation or PMR in reducing state anxiety after exposure to a transitory stressor. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Sandra Traint Andreas Pichler Robert Sierlinger Heinrich Pauli Ewald A. Werner 《国际钢铁研究》2006,77(9-10):641-649
To obtain the superior strength‐ductility‐balance of TRIP‐grades, a special chemical composition in combination with well adapted processing parameters are a prerequisite. Despite of their excellent formability performance in terms of drawability as characterized by high n‐ and elongation values, compared to mild steels TRIP‐grades are challenging in the press and the body shops. The high strength level in combination with the high work hardening of TRIP‐grades result in higher levels of spring back compared to mild steels and higher press forces are required. Furthermore, a higher sensitivity to failure for sharp bending radii and a deterioration of the formability of punched edges is reported for TRIP‐grades. While spring back can only be minimized by advanced forming processes supported by new simulation techniques with improved ability to predict spring back, the sensitivity to failure under special forming conditions can be influenced by optimizing microstructural features. Contrary to the forming behaviour, which is influenced significantly by the microstructure, the weldability is mainly governed by the chemical composition and the surface condition of the material. The high carbon content of TRIP‐grades compared to mild steels results in a higher hardening potential after welding. Additionally, a fracture behaviour untypical for mild steels after destructive testing of spot welds is sometimes observed for TRIP‐grades, which is assessed critically by some OEMs. In this work, after a discussion of the processing conditions, possibilities are demonstrated to improve the forming behaviour by an optimization of the microstructure and the spot weldability by adapting the chemical composition of low‐alloyed TRIP grades. First very promising results for TRIP‐grades with a minimum tensile strength level of 700 MPa are discussed. 相似文献
994.
Simpkins Sandra D.; Davis-Kean Pamela E.; Eccles Jacquelynne S. 《Canadian Metallurgical Quarterly》2006,42(1):70
This study addresses the longitudinal associations between youths' out-of-school activities, expectancies-values, and high school course enrollment in the domains of math and science. Data were collected on 227 youth who reported on their activity participation in 5th grade, expectancies-values in 6th and 10th grade, and courses taken throughout high school. Math and science course grades at 5th and 10th grade were gathered through school record data. Results indicated youths' math and science activity participation predicted their expectancies and values, which, in turn, predicted the number of high school courses above the predictive power of grades. Although there were mean-level differences between boys and girls on some of these indicators, relations among indicators did not significantly differ by gender. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Brown Sandra A.; Goldman Mark S.; Christiansen Bruce A. 《Canadian Metallurgical Quarterly》1985,53(4):512
Compared the reinforcement expectancies of adult alcoholics with beliefs of 2 other adult populations. 171 participants (mean age 42.8 yrs) in alcohol treatment programs, 65 hospitalized medical patients (mean age 42.6 yrs), and 344 college students (mean age 24 yrs) identified their beliefs about the consequences of alcohol consumption through an alcohol expectancy questionnaire (AEQ). Results indicate that the previously defined AEQ beliefs among nonalcoholic populations identified by S. A. Brown et al (1980) and B. A. Christiansen et al (see record 1982-25609-001) are applicable to alcoholic populations. In the present study, nonalcoholics and alcoholics differed significantly in terms of their alcohol expectancies. In general, alcoholics were found to maintain strong alcohol expectancies, and expectancies increased across and within populations as a function of drinking patterns. Theoretical, research, and clinical implications of these findings and the AEQ are discussed. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Organizing stories: Effects of development and task difficulty on referential cohesion in narrative.
Two experiments examined the effects of age and task difficulty on the referential cohesion of story retellings. In Exp I, analyses of referential error rates showed that 20 4-yr-olds produced more inappropriate introductory phrases than did 20 6-yr-olds, though rates for ambiguities in already-introduced referents did not differ significantly. Other types of referential errors were infrequent. Exp II investigated the impact of task difficulty on referring by systematically varying mode of story presentation (verbal vs video), familiarity/practice (1 vs 3 presentations), and S's cognitive style (reflective vs impulsive) as measured by the Matching Familiar Figures Test. It was hypothesized that increased task difficulty would lead to higher error rates for all S groups: 16 1st graders, 16 3rd graders, and 16 college students. Results indicate a higher incidence of errors with videotape rather than verbal presentation and for Ss with an impulsive style. Practice lowered the rate of introductory problems for young children, as expected, but failed to affect ambiguity rates. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Contends, based on a constructionist position on epistemology, that scientific knowledge (and knowledge of all kinds) is a construction of the human mind. Meaning is attributed to sensory data in theoretically guided inventions of "facts." At different times and places, facts invented in one theory become different facts in another. In each generation, psychologists have favored variables that serve loyally within the theoretical boundaries of the scientific wisdom of that time. It is argued that favored variables can blind scientists to other theories and other variables that could compete for favor. What makes theories and facts plausible is examined, and a continuum of persuasion, determined by the contexts of the theorists is proposed. Contemporary research on lead exposure and on parent–child interaction are examined as examples of facts that can become different facts in other theories. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Examined the alcohol expectancies of 321 17–40 yr old undergraduates as a function of Ss' drinking patterns and Ss' expectancies to demographic/background variables for their ability to predict problematic and nonproblematic drinking patterns. Ss completed a demographic data sheet, alcohol expectancy questionnaire, and customary drinking record. Factor analysis of Ss' self-reported drinking yielded 3 drinking styles: nonproblematic social drinking, frequent drinking with alcohol-related problems, and contextually determined alcohol consumption. Optimal alcohol expectancy and demographic/background predictors of each drinking style were selected and compared via multiple regression procedures. Predictor equation efficiency was then examined in a new cross-validation sample of 176 Ss. Results indicate that alcohol expectancies increased the predictability of college drinking patterns and that alcohol expectancies were differentially related to problematic and nonproblematic features of college drinking. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Investigated the interaction between postural regulation and spatial processing by having 24 college students perform L. R. Brooks's (see record 1968-04936-001) spatial and nonspatial memory tasks either while sitting or while maintaining a difficult standing balance position. The balance task disrupted spatial but not nonspatial memory performance. Balance steadiness during spatial and nonspatial memory conditions did not differ. Results suggest that cognitive spatial processing may rely on neural mechanisms that are also required for the regulation of posture. Findings support the idea that spatial processing may rely on phylogenetically older systems. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Glueckauf Robert L.; Stine Curtis; Bourgeois Michelle; Pomidor Alice; Rom Pilar; Young Mary Ellen; Massey Angela; Ashley Pat 《Canadian Metallurgical Quarterly》2005,50(4):346
Objective: To describe the challenges faced by rural caregivers in providing assistance to older family members with Alzheimer's disease and closely related conditions. Procedure: Preliminary focus group findings from a new grant initiative, Alzheimer's Rural Care Healthline, that assesses the efficacy of telephone-based cognitive- behavioral intervention for rural dementia caregivers. Groups identified specific caregiver educational and skills-training requirements and best methods for soliciting referrals from rural health providers, community elder care agencies, and churches. Results: Trust emerged as an overarching theme, along with family and community privacy issues and the stigma associated with dementia. Conclusions: Future studies should consider the educational priorities, technological requirements, and sociocultural context of rural caregivers in designing telehealth-based interventions, including issues of privacy, stigma, and trust. Recognition of these factors may lead to increased acceptability, frequency of use, and sustainability of rural telehealth programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献