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991.
992.
Bilingualism and education. 总被引:1,自引:0,他引:1
The concept of bilingualism as applied to individual children and to educational programs is discussed, and the history of research on bilingual children and bilingual education programs in the United States is reviewed. Bilingualism has been defined predominantly in linguistic dimensions despite the fact that bilingualism is correlated with a number of nonlinguistic social parameters. The linguistic handle has served policymakers well in focusing on an educationally vulnerable population of students, but the handle is inadequate as the single focus of educational intervention. Future research will have to be directed toward a multifaceted perspective of bilingualism as a phenomenon embedded in society. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Effects of ethnicity on treatment attendance, stimulant response/dose, and 14-month outcome in ADHD.
Arnold L. Eugene; Elliott Michael; Sachs Larry; Bird Hector; Kraemer Helena C.; Wells Karen C.; Abikoff Howard B.; Comarda Anne; Conners C. Keith; Elliott Glen R.; Greenhill Laurence L.; Hechtman Lily; Hinshaw Stephen P.; Hoza Betsy; Jensen Peter S.; March John S.; Newcorn Jeffrey H.; Pelham William E.; Severe Joanne B.; Swanson James M.; Vitiello Benedetto; Wigal Timothy 《Canadian Metallurgical Quarterly》2003,71(4):713
From the Multimodal Treatment Study of Children with Attention- Deficit/Hyperactivity Disorder--a randomized clinical trial of 579 children ages 7-9 years receiving 14 months of medication management, behavioral treatment, combination, or community care--the authors matched each African American and Latino participant with randomly selected Caucasian participants of same sex, treatment group, and site. Although Caucasian children were significantly less symptomatic than African American and Latino children on some ratings, response to treatment did not differ significantly by ethnicity after controlling for public assistance. Ethnic minority families cooperated with and benefited significantly from combination (multimodal) treatment (d = 0.36, compared with medication). This incremental gain withstood statistical control for mother's education, single-parent status, and public assistance. Treatment for lower socioeconomic status minority children, especially if comorbid, should combine medication and behavioral treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
In an earlier paper we introduced an indirect binary n-cube memory server network which has adaptive properties making it useful in a parallel vector processing environment. The memory server network, due to a special choice in the design of the basic switch node, has the property that N vector processors issuing vector fetches with similar strides are forced into lock step after an initial startup investment.
In this paper we extend this work to the case of the indirect k-any n-cube. As this network has a more favorable memory latency scaling of logkN, one expects that the short vector performance will be improved as k is increased for a given N. We find this to be the case. We also find that the cost of the memory server system scales in a manner which prefers modest values of k above 2. 相似文献
996.
Tested the predictions of 3 models of coalition behavior. 120 graduate students played each of 4 games, rotating among the 5 player positions (including a veto player) between games. The games were played under 1 of 3 time pressure/default conditions: (a) no time pressure, (b) a condition such that the constant payoff to coalitions was lost if an agreement was not reached in 3 attempts, and (c) a condition such that the payoff for no agreement was fixed at 60 points for the veto player and 10 for the other players. The veto players' payoffs varied over games and tended to increase as play continued, at times approaching the entire payoff. Thus, the weighted probability (S. S. Komorita, 1974) and Roth-Shapley (A. E. Roth, 1977; L. S. Shapley, 1953) models were not supported; the core model received some support. The default conditions had little effect. The likelihood of socially beneficial behavior in competitively motivating situations is discussed. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Avshalom Mizrahi Joseph Arnan George Miller Zvi Liron Moshe Manai Yedidya Batus Eugene Rosenberg 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1976,26(3):160-166
A process for the production of Myxococcus xanthus TA (M. xanthus TA) antibiotic was scaled-up to bench and pilot plant scales. The process includes the following steps: (a) propagation of M. xanthus TA in cultures of up to 750 litres. After 4 days of growth the maximum antibiotic yield achieved was 24 units/ml supernatant, and the highest titres were obtained at a low oxygen absorption rate of 0.2; (b) processing of the clarified culture supernatant. Two methods were successfully piloted: the chloroform extraction method and the kaolin adsorption method. Both methods were followed by elution with 20% methanol in chloroform. The recoveries of antibiotic activity were 90% and 85% respectively by the two methods. The process described could be used for the large-scale preparation of the novel antibiotic of M. xanthus TA. 相似文献
998.
Argues that although E. F. Alf and N. M. Abraham's (see record 1972-22071-001) conclusion that for small samples, randomization tests may be considerably less powerful than the corresponding parametric tests is valid, it is applicable only to those experimental situations where a population has been randomly sampled. Where there is random assignment to treatments but not random sampling, as is frequently the case in psychological experimentation, power comparisons of parametric and randomization tests are inappropriate because parametric tests are then valid only to the extent that they approximate randomization tests. It is concluded that in experiments employing random assignment but not random sampling, one should use randomization tests, if possible, whether the sample is large or small. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Addressed the problem encountered in everyday memory of forgetting the location of an object intentionally stored in a special location for future retrieval in 3 experiments, using 127, 36, and 92 undergraduates, respectively. Exp I was designed to capture the phenomenon; Exp II was designed as a further test of whether unusual locations are harder to remember than common ones; Exp III tested a prediction that follows from the notion that the use of common locations benefits from the use of a generation-recognition strategy. Results support the hypothesis that such forgetting is likely to occur when 2 conditions are met at the time of encoding: (a) a judgment that the location is very memorable and (b) a judgment that the location is an unlikely one for the object. It is argued that an auxiliary generation-recognition strategy cannot be relied on when one forgets an unlikely location. It is suggested that the 2 conditions most likely to induce people to store things in unlikely locations are the desire to hide them from others and a misapplication of a distinctiveness theory of memory to associative recall. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
In a noisy setting, 20 male and 20 female college students worked at anagrams and proofreading to reduce their sensitivity to the adverse effects of noise. Ss were randomly assigned before training to a perceived own-control- or no-control-over-noise condition and to a constant or increasing rate-of-exposure-to-noise condition. All Ss heard noxious noise punctuated by silence while they worked. Those who believed their rapid button pressing produced the silence improved significantly at proofreading but not at anagrams. Rate of exposure did not affect training. Conditions governing the contributions of perceived environment controlling responses to behavior rehearsal are discussed. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献