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981.
Christopher L. Cunningham Dobrina M. Okorn Christine E. Howard 《Learning & behavior》1997,25(1):31-42
DBA/2J mice were exposed to a distinctive floor stimulus (CS+) and ethanol (2 g/kg) in a place conditioning paradigm. A different floor stimulus (CS?) was presented with saline. Mice injected just before or 30 min before CS exposure (Groups 0, ?30) showed conditioned place preference, whereas mice injected right after exposure to the CS (Group 5) displayed place aversion (Experiment 1). None of the other groups (?120, ?60, 15, 60) showed place conditioning. Handling and saline injection given just before or after CS exposure were unable to produce place conditioning (Experiment 2). However, there was a positive relationship between ethanol concentration (10% vs. 20%) and test performance, suggesting that peritoneal irritation influences place conditioning (Experiment 3). Overall, these findings support the suggestion that intraperitoneal injection of ethanol produces an initial short-duration aversive effect that is followed by a longer lasting positive motivational effect. 相似文献
982.
This paper describes some of the issues surrounding the development of tolerance in young children, including the need to recognise that children's moral development is closely tied to their cognitive development. The importance of the family and other adult models is recognised as children make progress in understanding the views and rights of others. Teaching the young child about tolerance should be embedded in an inclusive approach to curriculum and children given opportunities to make decisions and take responsibility for their own actions consistent with their evolving capabilities. 相似文献
983.
Objective setting and evaluation for learning in the affective domain are often neglected in educational programs, largely because affective learning is a poorly understood phenomenon. This is particularly problematic in nonformal science education facilities, which are uniquely suited to facilitate affective learning. To address this problem, a heuristic model of affective learning in nonformal educational facilities was developed. The model, referred to as the Meredith Model, displays a sequence of events occurring in the affective responses of learners in nonformal educational experiences and identifies factors which may influence individual events within this sequence. The model is proposed as a conceptual framework for gaining an increased understanding of affective learning and for making recommendations for practice of nonformal science education and for further research. J Res Sci Teach 34: 805–818, 1997. 相似文献
984.
A. K. Raychaudhuri 《Resonance》1997,2(12):55-65
In this article we briefly review the application of electrons in the field of microscopy. Two types of microscopes are discussed,
the electron microscope and the tunneling microscope. It is emphasized that in both the applications the electron behaves
as a quantum mechanical object. 相似文献
985.
Schoenecker Timothy S. Martell Kathryn D. Michlitsch Joseph F. 《Research in higher education》1997,38(4):479-495
This paper focuses on the effect that diversity has on the performance and satisfaction of student groups in a computer simulation project. Using structural equation modeling, we find evidence to support the contention of previous research that diversity negatively affects group satisfaction. This finding was strongest for undergraduate groups. While the relationship between diversity and performance is inconclusive, groups that are dominated by one person tend to have below average performance. 相似文献
986.
Psychological Expertise and the Role of Individual Differences: An Exploration of Issues 总被引:1,自引:0,他引:1
Rodney K. Goodyear 《Educational Psychology Review》1997,9(3):251-265
Cognitive scientists have suggested that individual differences are relatively unimportant in predicting who will become an expert in any particular domain. This stance is at variance with the admissions screening practices of graduate programs in professional psychology as well as with counseling psychology's individual differences tradition. The purpose of this article was to consider some of the issues involved on both sides of this apparent contradiction, with particular emphasis on expertise in professional psychology. I first examine some of the possible operational definitions of expertise in this domain. I then consider salient literature and conclude that there almost certainly are threshold levels of intellectual and interpersonal skills that trainees in professional psychology should have. Beyond these levels, though, it may be that motivation and persistence are the most important variables in predicting the eventual attainment of expertise in professional psychology. 相似文献
987.
Brian E. Clauser Melissa J. Margolis Stephen G. Clyman Linette P. Ross 《Journal of Educational Measurement》1997,34(2):141-161
Performance assessments are typically scored by having experts rate individual performances. The cost associated with using expert raters may represent a serious limitation in many large-scale testing programs. The use of raters may also introduce an additional source of error into the assessment. These limitations have motivated development of automated scoring systems for performance assessments. Preliminary research has shown these systems to have application across a variety of tasks ranging from simple mathematics to architectural problem solving. This study extends research on automated scoring by comparing alternative automated systems for scoring a computer simulation test of physicians'patient management skills; one system uses regression-derived weights for components of the performance, the other uses complex rules to map performances into score levels. The procedures are evaluated by comparing the resulting scores to expert ratings of the same performances. 相似文献
988.
Yuen Mantak Chung Y. B. Lee Queenie A. Y. Lau Patrick S. Y. Chan Raymond M. C. Gysbers Norman C. Shea Peter M. K. 《International Journal for Educational and Vocational Guidance》2020,20(3):653-676
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data... 相似文献
989.
K. P. Mishra A. P. Yadav Lilly Ganju 《Indian journal of clinical biochemistry : IJCB》2012,27(4):357-362
The Antarctic continent on the planet Earth is full of environmental extremes. It is considered as natural stress model. Therefore, the present study examined the effect of harsh environment on the certain salivary markers of 28th Indian Antarctic expeditioners. Thirty healthy men and women (median age 36 year; range 22–61 year) participated in this study. Parameters measured were salivary IgA (SIgA), IgM (SIgM), TGF-β and cortisol level at three different time points: (I) before leaving India on 26th October 2008 for base line level; (II) after 1 month on-board journey on 31st January 2009 in Southern Ocean and (III) after 1 month staying at Maitri, Antarctica on 3rd March 2009. Our observation indicated that Ship borne journey and Antarctic environment increased the SIgA levels while that of SIgM level was not altered on-board but decreased by staying for 1 month at Antarctica. No significant alteration was found in the TGF-β and cortisol level at any point of time. The present study concluded that ship borne journey and Antarctic environment may induce the SIgA level while SIgM level decreased in environmental extremes of Antarctica. 相似文献
990.
E.E. Gdoutos 《Journal of The Franklin Institute》1981,312(5):361-371
An analysis of the plastic enclaves developed around the end points of rigid fiber inclusions embedded in an elastic plate is undertaken. The plate is subjected to a uniform uniaxial stress at any angle of inclination with the axis of the fiber. It is assumed that the material of the plate is elastic-perfectly plastic and that the deformations are small. A singular solution of the stress field in the vicinity of the end points of the fiber is used in conjunction with the Mises yield criterion to obtain the radius of the plastic zone under conditions of plane strain and generalized plane stress. The dependence of the size and shape of the plastic deformation on the orientation of the fiber, the Poisson's ratio of the plate and the state of stress (plane strain or generalized plane stress) is established. 相似文献