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841.
There has been a paucity of research that has investigated whether skilled performers of a complex sports skill can readily change their technique. This study was designed to investigate whether swimmers skilled in the conventional breaststroke technique could adjust readily to the wave action technique. Nine masters swimmers with well established and stable movement patterns for the conventional technique were coached in the wave action breaststroke technique. The swimmers were videotaped from the side during maximum speed trials of the conventional breaststroke technique before coaching and the wave action technique after ten 45-minute coaching sessions. The amplitude and phase of the waveforms comprising the vertical displacements of the body parts were determined by Fourier analysis. In response to the coaching, the amplitude of the fundamental frequency of the vertex of the head, shoulders, hips, and knees increased significantly (p < 0.01). The percentage of power contained in the fundamental frequency of the shoulder and hip vertical displacements also increased significantly (p < 0.01). All subjects changed the relative phase of the fundamental frequencies of the vertex, shoulder, and hip vertical displacements. It was concluded that in this complex skill, major changes to the low frequency waveforms comprising the motion were achieved readily. 相似文献
842.
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
843.
844.
Although there is considerable empirical support for the existence of social stereotypes about different types of mothers, the content of those stereotypes is less clear. The purpose of this study was to identify the content of stereotypes related to different types of mothers. Stereotyped attributes of married mothers, stepmothers, divorced mothers, and never married mothers were generated by several samples and combined into one list. A subsequent sample was asked to indicate the percentage of each type of mother possessing each characteristic. The content of mother stereotypes was examined, and the results discussed in light of effects on social interactions, the self-image of women, and future attempts to assess family-related stereotypes. 相似文献
845.
Size and orientation of objects in explicit and implicit memory: A reversal of the dissociation between perceptual similarity and type of test 总被引:3,自引:0,他引:3
H. D. Zimmer 《Psychological research》1995,57(3-4):260-273
Memory of size and orientation of objects was tested in explicit and implicit memory tests. Explicit memory was tested by object recognition and by recognition of the congruency of the changed sensory features. Implicit memory was tested by size assessment (Exps. 1 and 2), orientation judgement (Exps. 4 and 5), picture-fragment naming (Exp. 6), and classification (Exps. 3 and 7). Memory of sensory features was investigated by the comparison of performances of test-congruent with test-incongruent stimuli (i.e., same size or orientation vs. different size or orientation). The main result was a dissociation between these two tasks pertaining to the influence of sensory congruency on performance. However, it was in opposition to the usual relationship between the type of test and the perceptual similarity from study to test. In this study explicit, but not implicit, memory depended on sensory congruency. In the explicit tests performances were better when the stimuli were congruent than when they were incongruent. In the implicit test this variation had no influence. To get a repetition effect, it was important only that the object was repeated, and the size of this effect did not depend on sensory congruency. However, a change in another sensory feature — distortions of shape — strongly influenced the size of the repetition effect in the implicit test. Neither transfer-appropriate processing nor a system approach can easily explain this pattern of results. A multi-level, multi-token model is proposed to account for the different effects of sensory features in explicit and implicit memory. 相似文献
846.
MATERNITY LEAVE AND WOMEN'S MENTAL HEALTH 总被引:4,自引:0,他引:4
Janet Shibley Hyde Marjorie H. Klein Marilyn J. Essex Roseanne Clark 《Psychology of women quarterly》1995,19(2):257-285
The Wisconsin Maternity Leave and Health Study addresses an important policy issue, parental leave, by investigating the work status, maternity leave, and mental health of 570 women. In the longitudinal design, the women, all of whom were living with a husband or partner, were interviewed during the fifth month of pregnancy, 1 month postpartum, and 4 months postpartum. At 4 months postpartum, full-time workers, part-time workers, and homemakers did not differ in depression or anger, but full-time workers showed elevated anxiety compared with the other two groups. In multiple regression analyses, length of leave interacted significantly with marital concerns when predicting depression; women who took a short leave (6 weeks or less) and were high on marital concerns had the highest depression scores. Short maternity leave can be conceptualized as a risk factor that, when combined with other risk factors such as marital concerns, places women at greater risk for depression. 相似文献
847.
Supervisors representing different levels of experience viewed videotape vignettes of counselors demonstrating the first three developmental levels of Stoltenberg's (1981) Counselor Complexity Model. Supervisors assessed each counselor on his or her developmental level and on the supervision environment he or she would provide for the trainee. Results indicated that supervisor experience did not influence the assessment of developmental level or the ability to make accurate environmental matches. Nevertheless, supervisors had the most difficulty accurately assessing counselors representing Level 2 in Stoltenberg's model and tended to make relative judgments about counselor developmental level. Implications for training and further research are discussed. 相似文献
848.
Robert H. Pate 《Journal of counseling and development : JCD》1995,74(2):181-184
The guest editorial and featured articles have established the fact of counseling specialties and also that counselors have no clear or consistent scheme to recognize professional specialization. If counselors expect external recognition of and respect for their credentials, the credentials first must be recognized and understood by counselors. The experiences of other professions suggest strategies, but counselors must determine their own way of recognizing specialties without denying counselors' common identity. The profession and practice of counseling will be strengthened if all counselors have a minimum foundation of counseling knowledge and competencies and build accepted specializations on that foundation. The counseling profession must distinguish among work settings, professional interests, and specializations as a prerequisite to a coherent scheme of recognizing specialties. 相似文献
849.
With the end of the cold war, issues of environment and economic development are assuming greater international salience.
By the 1970s, environmental degradation was becoming pervasive, with growing global effects. Increasingly, global and emergent
globalized problems are forcing environmental interdependence on the world. Transboundary threats cannot be addressed unilaterally
by any single country or group of countries. The global environmental agenda is reviving the North-South debate and rejuvenating
the Third World coalition in international fora.
The encouragement of environmentally sustainable forms of industrialization in the South requires expanded and improved international
cooperation. However, the North’s greater resources and greater responsibility in causing global environmental degradation
require its continuing involvement in the search for solutions, including ones applicable to newly industrializing countries.
In June 1992, the largest intergovernmental conference ever held was convened in Rio de Janeiro to address these issues: the
United Nations Conference on Environment and Development (UNCED, or the Earth Summit). It produced a consensus action plan
of about 700 pages: Agenda 21. Agenda 21 presents massive challenges for international cooperation as well as for national
and private actors and scientific and technical institutions. It reflects a complex configuration of demands for institutional
arrangements that support environmentally sustainable technical and socioeconomic change. One of the most consistent of the
Agenda 21 themes, and one of the most intractable issues, concerns “access to technology.” This can be as straightforward
as diagnosing and improving the efficiency of a production process in a small manufacturing firm, or as complex as engineering
a technological revolution in which production and consumption take place with virtually no material or energy loss to the
environment. The selection of entry points for action is a critical strategic problem as well as an important operational
issue.
In this paper I identify and describe new initiatives intended to improve the environmental performance of industry in the
South, and find that they largely aim to promote incremental industrial innovation through international technology transfer
and diffusion. This strategy raises many questions about how to promote effective technology transfer and diffusion.
This is a revised version of a paper prepared for the ORSTOM/UNESCO Conference “20th Century Science: Beyond the Metropolis,”
Paris, 19–23 Sept. 1994. 相似文献
850.
We conducted two experiments to investigate if college students would create false memories of childhood experiences in response to misleading information and repeated interviews. In both experiments we contacted parents to obtain information about events that happened to the students during childhood. In a series of interviews we asked the students to recall the parent-reported events and one experimenter-created false event. In the second experiment we varied the age at which we claimed the false event occurred. In both experiments we found that some individuals created false memories in these circumstances and in the second experiment we found no effect of age of attempted incorporation. In the second experiment we also found that those who discussed related background knowledge during the early interviews were more likely to create a false recall. Generalizations to therapy contexts are discussed. 相似文献