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11.
The development of verbal and spatial working memory was investigated with an interference paradigm. Memory spans were obtained from 3 groups (8-, 10-, and 19-yr olds) under 6 different conditions: Two primary memory tasks (1 verbal, 1 spatial) were administered in isolation and in conjunction with 2 versions of a secondary task. The primary tasks required recalling a series of visually presented digits and recalling the locations of Xs in a series of visually presented grids. The secondary tasks required reporting the color of the stimuli as they were presented using either a verbal or a spatial response. Analyses revealed that all age groups showed domain-specific interference (i.e., interference by a secondary task from the same domain as the primary task), but only the 8-yr-olds also showed nonspecific interference (i.e., interference by a secondary task from a domain different than the primary memory task), suggesting that at least some executive functions do not reach adult levels of efficiency until approximately age 10. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Petronko Michael R.; Harris Sandra L.; Kormann Russell J. 《Canadian Metallurgical Quarterly》1994,62(1):49
Reviews challenges associated with behavioral training approaches for individuals with mental retardation and mental illness in the community. Family and non-family facilitated training are considered. Professional practice issues are reviewed, and justification for multifactor behavioral assessment is offered. Future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
White Desiree A.; Craft Suzanne; Hale Sandra; Park T. S. 《Canadian Metallurgical Quarterly》1994,8(2):180
A. D. Baddeley, N. Thomson, and M. Buchanan (1975) suggested that articulatory rehearsal rate determines the amount of verbal material that can be maintained in working memory. In the current study, 12 children with spastic diplegic cerebral palsy (SDCP) and 38 normal children were tested on measures of articulation rate and memory span for 1-, 2-, and 3-syllable words. Across all conditions, articulation rate for the SDCP group was significantly slower than for the normal group; nonetheless, memory span was equivalent for both groups. This finding implies that covert rehearsal proceeded normally for the SDCP group, in spite of decrements in speech rate. Thus, the relationship between overt and covert rehearsal rates differs for children with SDCP compared with normal children. Findings from the current study further suggest that normal speech rates are not necessary for development of normal covert rehearsal rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Sandra Aparecida de Assis Pedro Fernandes Bruno Sommer Ferreira Joaquim MS Cabral Olga Maria Mascarenhas Faria Oliveira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):277-280
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry 相似文献
15.
The amounts of substances migrating from plastics into foodstuffs with high fat contents are in most cases higher than in foodstuffs with water contents. This increase in migration commonly is due to the higher solubility of the migrating organic compounds in fat compared to water. The increase in migration is not necessarily due to an increase in the substance's diffusion coefficient due to interactions between the fat and the plastic as is often assumed. Ethanol is a good simulant for fatty foods because it has little interaction with many plastics, e.g. polyolefins, migrants are readily soluble in it, and because it is easy to work with analytically. The utilizable limits of ethanol and ethanol/water mixtures as food simulants are developed from the physical background of diffusion. The use of ethanol and ethanol/water mixtures is supported by published experimental migration results. 相似文献
16.
Greater use of psychological research and practice knowledge in the formulation of social policy is necessary to enhance the well-being of U.S. citizens and communities. Although historically there are instances in which psychological and social science research and practice have had a substantial influence on federal policy, for the most part the relationships among research, practice, and policy have been tenuous. Three cases in which research has substantively influenced policy over the past 80 years are reviewed: Keynesian economics, Head Start legislation, and the activities of conservative think tanks. Several recommendations are made for ways in which psychologists can enhance their influence in the policy arena, including communicating directly with policymakers regarding relevant policy findings and knowledge gleaned from practice; conducting interdisciplinary, multilevel research as well as evaluation research (including qualitative data drawn from practice settings); and networking among researchers, practitioners, policy advocates, and social action groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
The permeability and lag time for a heterogeneous diffusion system, in which the diffusivity and partition coefficient for the diffusant are dependent on position, are formulated in terms of a linear asymptotic analysis. A repeated integration of the diffusion equation is used to obtain the time dependence of the total solute release into the receiver, Q(t). The asymptotic form of Q(t) is linear in time. The slope, and intercept of this linear asymptote with the time axis, respectively, give formulas for the steady-state permeability and lag time. These formulas are then applied to diffusion systems of multiple laminates, consisting of a series of different homogeneous slabs. Thus, for the first time, a concise treatment of diffusion in multiple laminates is obtained. The formulas are also applied to periodic laminates, consisting of a series of identical slabs, but with position-dependent diffusivity and partition coefficient. We found that the lag time can be well approximated by (nh))2/(6Deff), where n and h are, respectively, the number and thickness of individual lamella, and Deff is an effective diffusivity, for which a relation in terms of the local property distributions is obtained. This approximation becomes more accurate with increasing number of lamellae. At n = 5, the relative error is already within 4%. Finally a procedure is discussed for readily obtaining the lag time for periodic structures consisting of a serial repetition of a multi-laminate. 相似文献
18.
Liew Jeffrey; Eisenberg Nancy; Losoya Sandra H.; Fabes Richard A.; Guthrie Ivanna K.; Murphy Bridget C. 《Canadian Metallurgical Quarterly》2003,17(4):584
Relations of heart rate and skin conductance reactions to mildly evocative empathy-inducing slides with socioemotional functioning were examined for 154 children (mean age = 9 years, 5 months). In addition, maternal expressivity was tested as a moderator of these relations. Parents and teachers rated children's socioemotional functioning, and a behavioral measure of children's regulation was obtained. Boys who exhibited higher skin conductance and higher heart rate to slides depicting negative emotions were better regulated, less emotionally intense, and better adjusted than their peers. Furthermore, boys' regulation and adjustment were positively related to such physiological responding to negative slides if maternal negative expressivity was relatively low or moderate, but not high. Fewer findings were obtained for girls or for positive slides. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Guimond Serge; Dambrun Micha?l; Michinov Nicolas; Duarte Sandra 《Canadian Metallurgical Quarterly》2003,84(4):697
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.