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911.
SUPERVISORY MENTORING BY ADVISERS: RELATIONSHIPS WITH DOCTORAL STUDENT POTENTIAL, PRODUCTIVITY, AND COMMITMENT 总被引:2,自引:0,他引:2
A 2-year, three-panel (T1-T3) longitudinal study of 233 entering Ph.D. students examined the relationships between student potential for mentoring, (i.e., attitudes and objective abilities at entry (T1), mentoring functions used by the faculty adviser (T2,T3), and student research productivity and commitment (T3). Student potential was found to predict the amount of psychosocial mentoring, career mentoring, and research collaboration provided by the adviser. Psychosocial mentoring and collaboration were not related to student productivity or commitment after controlling for the students' entering abilities and attitudes. Career mentoring at T2 was negatively related to the students' affective commitment to their program at T3. Implications for our understanding of mentoring and future research are discussed. 相似文献
912.
Behavioral economics of concurrent ethanol-sucrose and sucrose reinforcement in the rat: effects of altering variable-ratio requirements. 总被引:2,自引:2,他引:0
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These experiments examined the own-price and cross-price elasticities of a drug (ethanol mixed with 10% sucrose) and a nondrug (10% sucrose) reinforcer. Rats were presented with ethanol-sucrose and sucrose, both available on concurrent independent variable-ratio (VR) 8 schedules of reinforcement. In Experiment 1, the variable ratio for the ethanol mix was systematically raised to 10, 12, 14, 16, 20, and 30, while the variable ratio for sucrose remained at 8. Five of the 6 rats increased ethanol-reinforced responding at some of the increments and defended baseline levels of ethanol intake. However, the rats eventually ceased ethanol-reinforced responding at the highest variable ratios. Sucrose-reinforced responding was not systematically affected by the changes in variable ratio for ethanol mix. In Experiment 2, the variable ratio for sucrose was systematically increased while the ethanol-sucrose response requirement remained constant. The rats decreased sucrose-reinforced responding and increased ethanol-sucrose-reinforced responding, resulting in a two- to 10-fold increase in ethanol intake. Experiment 3 examined the substitutability of qualitatively identical reinforcers: 10% sucrose versus 10% sucrose. Increases in variable-ratio requirements at the preferred lever resulted in a switch in lever preference. Experiment 4 examined whether 10% ethanol mix substituted for 5% ethanol mix, with increasing variable-ratio requirements of the 5% ethanol. All rats eventually responded predominantly for the 10% ethanol mix, but total amount of ethanol consumed per session did not systematically change. In Experiment 5, the variable-ratio requirements for both ethanol and sucrose were simultaneously raised to VR 120; 7 of 8 rats increased ethanol-reinforced responding while decreasing sucrose-reinforced responding. These data suggest that, within this ethanol-induction procedure and within certain parameters, demand for ethanol-sucrose was relatively inelastic, and sucrose consumption was independent of ethanol-sucrose consumption. Demand for sucrose, on the other hand, was relatively elastic, and ethanol-sucrose readily substituted for it. The results are discussed in terms of applying a behavioral economic approach to relationships between drug and nondrug reinforcers. 相似文献
913.
N. Jane Zbrodoff 《Memory & cognition》1995,23(6):689-700
In four experiments, the problem-size effect was investigated, using an alphabet-arithmetic task in which subjects verified such problems as A + 2 = C. Problem size was manipulated by varying the magnitude of the digit addend (e.g., A + 2, A + 3, and A + 4). The frequency and similarity of problems was also manipulated to determine the contribution of strength and interference, respectively. Experiment 1 manipulated frequency at low levels of practice and found that strength could account for the problem-size effect. Experiment 2 manipulated frequency at higher levels of practice, and found that strength alone could not account for the problem-size effect at asymptote. Experiment 3 manipulated frequency and similarity and found a substantial problem-size effect at asymptote, suggesting that both strength and interference contribute to the problem-size effect. Experiment 4 manipulated similarity, keeping frequency constant, and found no problem-size effect at asymptote, suggesting that interference alone is not responsible for the problem-size effect. The results are related to findings with number arithmetic. 相似文献
914.
Gilberto N. O. Brito Rita C. A. Pinto Mauro F. C. Lins 《Journal of abnormal child psychology》1995,23(4):509-520
A teacher scale based on DSM-III-R diagnostic criteria for attention deficit hyperactivity disorder (ADHD) was developed for the behavioral assessment of children in Brazil. A total of 2, 082 children (782 males and 1,300 females) with a mean age of 11.2 years who were attending a public school in the greater Rio de Janeiro area were the subjects of this study. Two factors (Hyperactivity-Impulsivity and Inattention) were extracted from a principal-factor analysis conducted on the data, and the factor structure of the scale was found to be stable. Ratings of boys were higher than ratings of girls, and younger children had higher ratings than older children for both factors. Test-retest reliability for each item of the scale ranged from .56 to .70. The data are discussed in view of current controversies in the factor structure of teacher ratings of DSM-III-R ADHD symptoms.This research was supported by FINEP (42.88.0138.00) and FUNPENE. GNOB is the recipient of a CNPq Research Career Development Award (30.0197/82). RCAP was supported by a CNPq fellowship (82.2151/87). The authors are grateful to Rosely V. Magalhaes and Angela S. Guedes for assistance in data analysis with the SAS and SPSS packages. The authors wish to thank the school staff and teachers who participated in the study. This work was presented at the Fifteenth European Conference of the International Neuropsychological Society, Portugal, 1993. 相似文献
915.
Michelle Bidaut-Russell Wendy Reich Linda B. Cottler Lee N. Robins Wilson M. Compton Richard E. Mattison 《Journal of abnormal child psychology》1995,23(5):641-659
To identify reasons for discrepancies between parent and child reports of child/adolescents's psychiatric symptoms, parents and adolescents (51 pairs) were asked to guess what the other would answer to questions from the PC-DISC about the adolescent's psychiatric symptoms, and to explain why they expected disagreement when the answer they provided for the other was different from their own. Adolescents' explanations for expecting (1) parental denial of symptoms the adolescent reported were: the parent was unaware of, forgot about, assumed the adolescent could not have, or trivialized the symptom; and (2) parental report of symptoms the adolescent denied were: the parent misread or exaggerated the adolescent's symptom, had too high expectations for the adolescent's behavior, put a negative label on or did not trust the adolescent. Parents' reasons for expecting their children to (1) deny symptoms the parents reported were: the adolescent did not remember how s/he felt, lied, did not recognize or minimized the importance or frequency of the symptom; and (2) report symptoms the parents denied were: the adolescent lied, exaggerated the importance of or interpreted the symptom differently.Support for this work was provided by National Institute of Drug Abuse grant number DA-05585 (Dr. Cottler, P.I.), and National Institute of Mental Health grants numbers MH-31302 (Dr. R. C. Cloninger, P.I.) and MH-17104 (Dr. Cottler, P.I.).Address all correspondence, including reprint requests, to Michelle Bidaut-Russell, Ph.D, MPH, MPE, Department of Psychiatry, Box 8134, Washington University School of Medicine, 4940 Children's Place, St. Louis, Missouri 63110. 相似文献
916.
The relationship between locus of control and long-term stuttering treatment outcome in adult stutterers 总被引:1,自引:0,他引:1
The present study was designed to investigate the extent to which adult stutterers' scores on the Locus of Control of Behaviour (LCB) scale are predictive of their ability to maintain speech fluency immediately following intensive treatment and approximately 2 years later. Twenty-one subjects participated in a 3-week intensive treatment program based on the Precision Fluency Shaping Program. Thirteen subjects could be contacted again 2 years later to participate in a follow-up evaluation. While most subjects showed a significant long-term improvement in fluency, no predictive relationship was found between scores on the LCB scale and the level of fluency, measured in percentage of words stuttered, post-treatment or at follow-up. However, LCB scores were found to be predictive of the subjects' fluency self-evaluation measured post-treatment and at follow-up. Overall, the present study suggests that while the LCB scale may contribute to the prediction of long-term treatment outcome, particularly as perceived by the client, other client and process variables will need to be considered as well. 相似文献
917.
Elena F. Brand Brian Lakey Shirley Berman 《American journal of community psychology》1995,23(1):117-135
Investigated the effects of a 13-week preventive, psychoeducational intervention program to improve perceived social support.
Fifty-one, low-perceived support, community residents were randomly assigned to an intervention or wait-list control condition.
Intervention subjects received training in social skills and cognitive reframing regarding the self and social relations.
The intervention led to increased perceived social support from family, but not from friends. As hypothesized by social cognition
models, increases in perceived support appeared to be mediated by changes in self-esteem and frequency of self-reinforcement.
Further, such changes in cognition about the self were larger than the changes observed for perceived support, suggesting
that it may be easier to change cognition about the self than perceptions of support. 相似文献
918.
ABSTRACT Biomedical experimentation on animals is justified, researchers say, because of its enormous benefits to human beings. Sure, animals suffer and die, but that is morally insignificant since the benefits of research incalculably outweigh the evils. Although this utilitarian claim appears straightforward and relatively uncontroversial, it is neither straightforward nor uncontroversial. This defence of animal experimentation is likely to succeed only by rejecting three widely held moral presumptions. We identify these assumptions and explain their relevance to the justification of animal experimentation. We argue that, even if non-human animals have considerably less moral worth than humans, experimentation is justified only if the benefits are overwhelming. By building on and expanding on arguments offered in earlier papers, we show that researchers cannot substantiate their claims on behalf of animal research. We conclude that there is currently no acceptable utilitarian defence of animal experimentation. Moreover, it is unlikely that there could be one. Since most apologists of animal experimentation rely on utilitarian justifications of their practice, it appears that biomedical experimentation on animals is not morally justified . 相似文献
919.
Mary Turner DePalma Scott F. Madey Susan Bornschein 《Personality and individual differences》1995,18(6)
To examine whether guilt would inhibit immoral behavior, subjects were differentiated on their feelings of anticipatory (AG) and posttransgressional (PTG) guilt and subsequently placed in an anagram task shown to induce a high level of cheating. Results indicated that neither pre- nor post-test AG was related to cheating behavior, and test-retest administration indicated that the AG scale was unreliable. The PTG scale, however, was found to be a temporally reliable measure of guilt. In order to assess the relative contributions of pre-test posttransgressional guilt, the ability to persist, and gender to cheating behavior, a saturated multiple regression model of centered predictor effects and interaction terms was constructed. Results revealed a significant gender × persistence interaction. The cheating behavior of males was not significantly influenced by the ability to persist. On the other hand, females who exhibited a strong ability to persist rarely cheated, while those who were unable to persist cheated a great deal. Finally, subjects who felt the most posttransgressional guilt cheated more frequently. These findings provide additional evidence that guilt may be positively related to cheating behavior. 相似文献
920.