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961.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
962.
This paper presents an analysis, based on simulation, of the stability of principal components. Stability is measured by the expectation of the absolute inner product of the sample principal component with the corresponding population component. A multiple regression model to predict stability is devised, calibrated, and tested using simulated Normal data. Results show that the model can provide useful predictions of individual principal component stability when working with correlation matrices. Further, the predictive validity of the model is tested against data simulated from three non-Normal distributions. The model predicted very well even when the data departed from normality, thus giving robustness to the proposed measure. Used in conjunction with other existing rules this measure will help the user in determining interpretability of principal components.The authors would like to thank the four anonymous reviewers and the two editors for their valuable comments. Atanu R. Sinha gratefully acknowledges the research support received from the Marketing Studies Center, AGSM, UCLA. Send requests for reprints to Atanu R. Sinha, B418 Gold Hall, 110 Westwood Plaza, Los Angeles, CA 90095.  相似文献   
963.
There are at least two qualitatively different types of subjective experience that can accompany accurate recognition memory. Sometimes recognition is accompanied by conscious recollection of the learning episode (i.e., it isremembered), and in other cases it is not (i.e., it is simplyknown that the item is old). In the present study, we assessed the subjective experience that accompanies crossmodality confusion errors (misidentifying words as pictures) by measuring the extent to which subjects claimed toremember versusknow that the item was presented as a picture. The results of two experiments demonstrate that cross-modality confusion errors are often accompanied by conscious recollection, although not to the same extent as accurate memories. The findings also show that there is considerable overlap in the recollective experience that accompanies accurate and erroneous memories. Finally, the results support the contention that recollective experience cannot be directly inferred from test performance.  相似文献   
964.
The Child Behavior Checklist's (CBCL) applicability to a sample of 105 Russian 9- and 10-year-old children was evaluated by examining the internal consistency of Russian adaptations of parent and teacher report forms. In addition, child behavior scores were correlated with child reports of internalizing symptoms and maternal reports of their own internalizing symptoms and general family functioning. Finally, rates of child behavior problems and patterns of interrater agreement were compared with U.S. normative data. The psychometric properties of the adaptations demonstrate the adequacy of these instruments for use in Russia. Internal consistency and interrater agreement were generally comparable to estimates obtained in U.S. normative samples. Further, an exploration of the construct validity of the Russian versions of the CBCL and Teacher Report Form (TRF) lends additional support to the adequacy of these instruments.This work was supported in part by grants from the International Research Exchanges Board (IREX) (with funds provided by the Andrew Mellon Foundation, the National Endowment for the Humanities, and the U.S. Department of State) and the National Institute of Mental Health (MH-00508, an RSDA to D. Pauls). None of these organizations is responsible for the views expressed. In addition, the authors wish to thank Thomas Achenbach for his helpful comments and suggestions.  相似文献   
965.
966.
Crisis intervention has typically been conceptualized as seeking a return of clients to a state of equilibrium. Our work with Hurricane Andrew survivors in south Florida, as part of the Disaster Mental Health Services team of the American Red Cross, has led us to appreciate the importance of several further considerations. In our work, we developed a proactive approach, attempting to recognize and extend clients' preexisting strengths. We offer a number of pragmatic interventions, focusing particularly on children's issues and we draw attention to sensitive multicultural issues.  相似文献   
967.
Abstract— Two experiments tested college students in a delayed matching-to-sample procedure designed to explore how multiple competitive sources of control interact in determining choice behavior. The primary sources of potential control were the frequency with which each of two colors was correct (base rates) and the accuracy of a sample in predicting the correct choice (accuracy rate). In one experiment, subjects ignored the base rates, and therefore made nonoptimal choices. These results mimicked the well-known base-rate error found in verbal responses to questions. In a second experiment, manipulations to increase subjects' motivation did not alleviate the error significantly. Together, these results suggest that the base-rate error may represent a broad behavioral pattern not restricted to verbal arenas. The results are compared with previous attempts to reconcile behavioral and cognitive lines of experimentation.  相似文献   
968.
Book reviews     
Gott ist schön und Er liebt die Schönheit: God is Beautiful and He Loves Beauty. Alma Giese and J. Christoph Bürgel, 1994. Bern, Peter Lang. 474 pp., hb. n.p., ISBN 3–906750–90–6.

The Concept of Islamic International Criminal Law. Farhad Malekian, 1994. London, Graham & Trotman. 213 pp., £55.00, $92, ISBN 1859660851.

Religion in Europe: contemporary perspectives. S. Gill, G. D'Costa, and U. King (Eds), 1994. Kampen, Kok Pharos. 213 pp., pb., Fl 49.90, ISBN 90–390–0508–7.

Religious Freedom and the Position of Islam in Western Europe. W. A. R. Shadid and P. S. van Koningsveld, 1995. Kampen, Kok Pharos. 229 pp., pb., Fl 64.90, ISBN 90–390–0065–4.

Christianity in the Arab World. HRH Crown Prince El Hassan Bin Talal, 1994. Amman, Arabesque. 120pp., hb.

Holymen of the Blue Nile: the making of an Arab‐Islamic community in the Nilotic Sudan 1500–1850. Neil MHugh. Evanston Illinois, Northwestern University Press. 280pp., hb., $54.95, ISBN 0–8101–1069–5.  相似文献   

969.
970.
The creation of embryos for research use has drawn a great deal of criticism. It is difficult to defend an ethical distinction between what one can do to "spare" embryos and what one can do to "research" embryos. The strongest ground on which to argue against the creation of embryos for research is a symbolic one, having to do with respect for human life. Ronald Dworkin's work in Life's Dominion on the symbolic meaning of the abortion debate throws a helpful light on this dispute. By understanding the basic question to be, Does the creation of research embryos weaken or insult our communal respect for the sanctity of human life in some way that in vitro fertilization (IVF) or the experimental use of "spare" embryos does not?, the debate can move in a more constructive direction.  相似文献   
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